Enviro nme ntal Manage me nt and He alth
8 / 2 [1997] 5 1 –6 6 © MCB Unive rs ity Pre s s [ISSN 0956-6163]
Environment and human health: a threat to all
Rajendra Ramlogan
Unive rs ity o f Cambridge , UK
Focuses on the direct and indirect impact of environ-mental abuse on human wellbeing. In some instances, the impact of environmental abuse on human health is not still unknown, merely being subject to scientifi c suspi-cion. This would suggest caution and the need for preventive measures to be applied. The threat to human health from environmental factors is not an isolated problem that exists on a national level. There are environmental factors that affect human health on a global level or are so wide-spread as to be considered global problems. Other envi-ronmental problems cross national boundaries and achieve regional importance.
Introduction
T h e wor ld t h a t w e in h a b it h a s b een s h a p ed la r gely by a ct s of n a t u r e a n d of m a n . T h e su b ject of t h e s h a p in g of t h e en v ir on m en t by n a t u r a l for ces a n d it s effect on m a n d oes n ot for m p a r t of t h is r ev iew. In s t ea d t h is p a p er is d ed ica t ed s olely t o a n a n a ly sis of t h e r ole of m a n in t h e a bu s e of t h e en v ir on m en t a n d t h e ext en t t o w h ich t h is a ffect s h u m a n h ea lt h a n d w ellb ein g. T h er e is a lon g lit a n y of m a n ’s m is u s e of h is en v ir on m en t , a n d ev id en ce sh ow s t h a t t h e s it u a t ion h a s wor s en ed d r a -m a t ica lly over t h e la s t 300 yea r s. T h e con fl ict a p p ea r s t o h ave in t en sifi ed , cr ea t in g con cer n t h a t w e m ay b e p u sh in g ou r selves t o t h e b r in k of a glob a l d is a st er. F a ct or s su ch a s t h e In d u st r ia l Revolu t ion of t h e m id -eigh t een t h cen t u r y, w h ich s t a r t ed in Br it a in a n d m a d e it s w ay t o E u r op e a n d N or t h Am er ica , a n d t h e in sa t ia ble a p p et it e for fu el, a n d t h e gr ea t t ech n ologica l s t r id es t h a t a ccom p a n ied t h e In d u st r ia l Revolu t ion , u r b a n iza t ion , t h e com -m er cia liza t ion of a gr icu lt u r e, t h e r is e in con s u m er is m , a n d p op u la t ion gr ow t h , h ave oft en b een h er a ld ed a s t h e t u r n in g p oin t for t h e m od er n cr is is t h a t h a s a r is en b et w een m a n a n d t h e en v ir on m en t . Yet d es p it e t h e ea r ly s t a r t t o en v ir on m en t a l p r oblem s, it is p er h a p s t r u e t h a t a s t h e t w en t iet h cen t u r y p r e p a r es t o give w ay t o t h e t w en t y -fi r s t , t h e fu ll s ca le of t h e h ea lt h im p lica t ion s of en v i-r on m en t a l d e gi-r a d a t ion h a s s t a i-r t ed t o b e r evea led .
Good h ea lt h h a s b een on e of t h e m a jor goa ls of h u m a n k in d t h r ou gh ou t t h e m a r ch of h is-t or y. T h e Wor ld H ea lis-t h Or ga n iza is-t ion (WH O) d efi n es h ea lt h a s t h e st a t e of com p let e p h y si-ca l, m en t a l a n d socia l w ellb ein g of m a n ; n ot m er ely fr eed om fr om d isea s e or in fi r m it y (Weis n er, 1992, p. 1). It h a s b een a r gu ed t h a t t h e b a s ic r eq u ir em en t s for a n a cce p t a ble level of h ea lt h a r e a s u it a ble d iet , d ecen t s h elt er, com p a n ion sh ip, a n a d eq u a t e in com e a n d a h ea lt h y en v ir on m en t . Im p or t a n t ly, good h ea lt h r eq u ir es a con s t r u ct ive b a la n ce b et w een in d iv id u a ls or gr ou p s a n d t h e en v i-r on m en t (Weisn ei-r, 1992, p p. 2-4). It is b ein g r ecogn ized t h a t t h e p h y sica l en v ir on m en t is t h e m ost im p or t a n t d et er m in a n t of good h ea lt h a n d , con s eq u en t ly, p r ot ect ion of t h e en v ir on m en t a n d p r es er va t ion of ecosy st em s
a r e fu n d a m en t a l in t h e s t r u ggle a ga in st h u m a n illn esses (Cor t ese, 1993, pp. 1-3). E xist-in g ev id en ce su ggest s t h a t t h e m ost ser iou s p ot en t ia l con s eq u en ce of glob a l en v ir on m en -t a l ch a n ge is -t h e d ecim a -t ion of -t h e E a r -t h ’s life-su p p or t sy st em s (McM ich a el, 1993, p. xiii). Cor t es e h a s a s ser t ed t h a t r a p id in d u s-t r ia l gr ow s-t h , s-t h e p op u la s-t ion exp los ion , r esou r ce d e p let ion , a lt er a t ion of t h e ch em ica l com p osit ion of t h e a t m os p h er e a n d t h e cyclin g of ca r b on , n it r ogen a n d p h os p h or ou s a r e fa ct or s la r gely r esp on sible for a lt er in g t h e b a sic p h y siology of t h e E a r t h (Cor t ese, 1993, p. 2; God lee a n d Wa lk er, 1992, p p. 1-8). In t h e wor d s of M cMich a el (1993), it wou ld a p p ea r “t h a t t h is fa b r ic of life-su p p or t in g m ech a n is m s is n ow s t a r t in g t o u n r avel, in a b r ief geologica l m om en t , a s t h e cu m u la t ive glob a l im p a ct of h u m a n a ct iv it y esca la t es” (p. 5)”.
On e of t h e in cr ea s in gly a p p a r en t fea t u r es of life in t h e la t t er h a lf of t h e t w en t iet h cen t u r y is t h e gr ow in g in t er d e p en d en cy of t h e glob a l v illa ge. T h is t r en d t ow a r d s a sm a ller, m or e a ccessible a n d in t er r ela t ed wor ld h a s ju st ifi -a b ly led t o m -a n y d iffer en t -a r e-a s of con cer n , on e of w h ich p er t a in s t o t h e en v ir on m en t . Develop in g a u n ifor m d efi n it ion of w h a t is m ea n t by t h e t er m “en v ir on m en t ” h a s p r oved elu sive. For p u r p oses of t h is p a p er, a wor k in g d efi n it ion of t h e en v ir on m en t sh a ll r efer t o: • t h e p h y sica l elem en t s of t h e E a r t h , n a m ely
t h e a ir, w a t er, la n d su r fa ce, su b -su r fa ce st r a t a (t oget h er w it h a ll liv in g r esou r ces t h er ein );
• ou t er sp a ce;
• a m b ien t b a ck gr ou n d a n d h u m a n h a b it a -t ion s;
• t h e wor k p la ce;
• in d igen ou s p eop les; a n d
• t h e n a t u r a l, cu lt u r a l a n d com m on h er it a ge of t h e wor ld .
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a s p ir a t ion s of h u m a n societ y for a b et t er fu t u r e. T h u s, a s t h e con fl ict b et w een m a n a n d t h e en v ir on m en t in t en sifi es, it wou ld b e w is e t o b ea r in m in d t h a t t h e h u m a n b ody m ay p ay t h e u lt im a t e p r ice for t h e in d iscr et ion s of t h e h u m a n r a ce.
Environmental degradation and
human health: the global village
Global warming
Clim a t e ch a n ge is d est in ed t o a ffect t h e en t ir e glob a l v illa ge a s it is a p la n et a r y occu r r en ce. A w a r m er wor ld is for eca st a s a r es u lt of t h e effect s of gr een h ou s e em iss ion s. It is n ow t h ou gh t t h a t h u m a n h ea lt h m ay b e a ffect ed by glob a l w a r m in g. Un d er w a r m er con d i-t ion s, h ea i-t si-t r es s r ela i-t ed con d ii-t ion s m ay b ecom e m or e com m on , lea d in g t o in cr ea ses in m or b id it y a n d m or t a lit y (Lon gst r et h , 1990, p. 525; Sch n eid er, 1989, p. 182). Wa r m er s u m -m er s -m ay p r od u ce h igh er in fa n t a n d foet a l m or t a lit y d u e t o su m m er t im e in cr ea ses in in fect ion s (Lon gs t r et h , 1990, p. 525). Mois t er a n d w a r m er con d it ion s wou ld fa cilit a t e t h e n or t h w a r d s p r ea d of in s ect -b or n e d is ea s es, for exa m p le, fr om m osq u it oes a n d t ick s (Sch n eid er, 1989, p. 182). On e p oss ible d is ea s e t h a t m ay fl ou r ish u n d er con d it ion s of glob a l w a r m in g is m a la r ia . Ad d it ion a lly, w a r m er a n d m ois t er con d it ion s m ay lea d t o h igh er r a t es of s k in in fect ion s (Lon gs t r et h , 1990, p. 525).
Depletion of the stratospheric ozone layer An ot h er en v ir on m en t a l p r oblem w it h glob a l con seq u en ces is t h e d e p let ion of t h e st r a t os -p h er ic ozon e layer, a n d h er e h u m a n h ea lt h m ay ver y w ell p r ove t o b e t h e m os t d ir ect ca s u a lt y. E xp osu r e t o u lt r av iolet -B r a d ia t ion ca n ca u s e a su p p r ess ion in im m u n e sy st em s lea d in g t o a n in cr ea se in in fect ion s (Mor is on , 1992, p. 49). Ad d it ion a lly, t h er e m ay even b e a p oss ible d ecr ea se in t h e effect iven es s of va c-cin es (UN E P, 1990, p. 116). Sk in p igm en t a t ion wou ld n ot p r ot ect a ga in st d efi cien cies in t h e im m u n e sy st em , s o r en d er in g p er son s in t h e t r op ics eq u a lly a t r isk (Ilya s, 1989; J eeva n a n d Kr ip k e, 1993, p. 1160).
E n h a n ced levels of u lt r av iolet -B r a d ia t ion ca n lea d t o in cr ea sed d a m a ge t o t h e eyes, lea d in g t o a h igh er in cid en ce of ca t a r a ct s. Ca t a r a ct s ca n im p a ir v ision a n d even ca u s e blin d n es s. It h a s b een es t im a t ed t h a t t h e in cid en ce of ca t a r a ct s wou ld in cr ea se by 0.6 p er cen t p er 1 p er cen t ozon e d e p let ion . T h is m ay r es u lt in a n a d d it ion a l 100,000 ca ses of blin d n es s wor ldw id e (UN E P, 1990, p. 116). Wit h r es p ect t o ot h er ocu la r a ilm en t s, it is a n t icip a t ed t h a t t h er e wou ld b e a r is e in ca s es of k er a t o-con ju n ct iv it is or s n ow blin d n es s.
F in a lly, lon g-t er m in cr ea ses in u lt r av iolet -B ir r a d ia n ce w ill en h a n ce t h e r isk of n on -m ela n o-m a sk in ca n cer (M a d r on ich a n d De Gr u jl, 1994, p p. 541-6). It is p r oject ed t h a t ever y 1 p er cen t d ecr ea s e in t h e t ot a l ozon e colu m n w ill r esu lt in a 3 p er cen t r is e in t h e in cid en ce of n on -m ela n om a ca n cer (Diffey, 1992, p p. 2267-79; UN E P, 1990, p. 116). Ca ses of t h e m or e d a n ger ou s m a lign a n t m ela n om a a r e a ls o a n t icip a t ed (H en r ik sen et a l., 1990, p p. 57982; J on es, 1989, p. 213). Ult r av iolet B r a d ia -t ion ca n in cr ea se m or -t a li-t y a n d m or b id i-t y sign ifi ca n t ly t h r ou gh m ela n om a a n d n on -m ela n o-m a sk in ca n cer s. On a les s ser iou s level t o sk in ca n cer, u lt r av iolet -B r a d ia t ion ca n a lso r es u lt in a cu t e er y t h em a or su n bu r n , a con d it ion t h a t w ill esp ecia lly a fflict ligh t sk in n ed p eop le (J on es, 1989, p. 208). T h e effect of ozon e d e p let ion wou ld b e t o sh ift p op u la t ion s closer t o eq u a t or ia l con d it ion s of u lt r a -v iolet exp osu r e t h a n gen et ica lly p er m issible (J on es, 1989, p. 215). Develop in g cou n t r ies w it h a lr ea dy u n d er d evelop ed h ea lt h -ca r e sy st em s wou ld su ffer t r em en d ou sly if t h er e is a n u p su r ge in in fect ion r a t es or ca t a r a ct for m a t ion (Tolb a a n d E l-Kh oly, 1993, p. 34).
M arine resource
T h e t h r ea t t o t h e ocea n s by p ollu t ion is ca p a -ble of cr ea t in g h avoc t h r ou gh ou t t h e wor ld . P ollu t ion of ocea n s or igin a t es fr om m a n y sou r ces. Tod ay over 60 p er cen t of t h e wor ld ’s p op u la t ion live w it h in t h e v icin it y of a coa st -lin e, w it h t wo-t h ir d s of t h e wor ld ’s cit ies w it h p op u la t ion s of m or e t h a n 2.5 m illion sit u a t ed n ea r est u a r ies (Tolb a a n d E l-Kh oly, 1993, p. 107). T h is h igh level of p op u la t ion in t h e v icin it y of ocea n s h a s led t o t h e d ir ect d u m p -in g of m u n icip a l w a st es a t sea , w h er e ver y oft en liq u id a n d s em i-solid w a st es a r e sim p ly p u m p ed t h r ou gh sh or t p ip es (Wh it e, 1993, p. 87). Ad d it ion a lly, m a n ’s u se of t h e ocea n s h a s led t o p ollu t ion fr om w it h in t h e ocea n . It is est im a t ed t h a t a p p r oxim a t ely 6.4 m illion t on s of gen er a l s h ip b oa r d lit t er a r e d u m p ed a n n u a lly by sh ip s a t sea (Tolb a a n d E l-Kh oly, 1993, p. 120). F u r t h er, ocea n u ser s m a in ly in volved in t h e fi s h in g in d u s t r y gen er a t e 136,000 t on s of p la st ic, n et s, lin es a n d bu oy s a n d 22,000 t on s of p la st ic con t a in er s, a ll of w h ich con t r ibu t e t o lit t er in g of t h e ocea n (Wh it e, 1993, p. 85).
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t r a n s p or t ed ou t in t o t h e s ea a n d d u m p ed . In r ecen t t im es, h a za r d ou s w a s t e w a s t r a n s -p or t ed t o sea a n d in cin er a t ed . As h es a n d ot h er con t a m in a n t s t h a t a r e n ot effect ively n eu t r a lized by in cin er a t ion a r e d u m p ed a t sea (Wh it e, 1993, p p. 86-7). F in a lly, offsh or e m in in g a ct iv it ies h ave con t r ibu t ed t o t h e p ollu t ion of t h e ocea n s. In T h a ila n d it h a s b een d is cover ed t h a t offsh or e t in m in in g h a s d e gr a d ed s ea w a t er q u a lit y a n d d a m a ged r eef ecos y st em s (Ru ya b h or n a n d P h a n t u m va n it , 1988, p. 229).
By fa r t h e gr ea t est h ea lt h t h r ea t fr om p ollu -t ion of -t h e wor ld ’s ocea n s com es fr om fi sh con t a m in a t ion . T h e Un it ed N a t ion s E n v ir on -m en t a l P r ogr a -m -m e (UN E P ) h a s es t i-m a t ed t h a t over 20 b illion t on s of w a s t e in clu d in g sew a ge, a gr icu lt u r a l r u n -off a n d in d u st r ia l w a s t e a r e d u m p ed in t o t h e ocea n a n n u a lly. Ap p r oxim a t ely 90 p er cen t r em a in n ea r coa st -lin es w h ich , t oget h er w it h r eefs p r ov id e a r ou n d 95 p er cen t of t h e wor ld ’s fi sh ca t ch (Tolb a a n d E l-Kh oly, 1993, p. 117; Wh it e, 1993, p. 87). F is h con t a m in a t ion ca n h ave ser iou s h ea lt h im p lica t ion s. T h e con s u m p t ion of con t a m in a t ed sea food ca n lea d t o s er iou s h ea lt h p r oblem s, p a r t icu la r ly in d evelop in g cou n t r ies w h er e, a s n ot ed b efor e, t h e ocea n s p r ov id e t h e m a jor sou r ce of p r ot ein . T h e Min im a t a m er cu r y p oison in g in cid en t in J a p a n is a n exa m p le of t h e a dver s e con se-q u en ces of con su m in g con t a m in a t ed sea food (Wh it e, 1993, p p. 85-6). In Min im a t a m er cu r y w a s t e p r od u ced by a loca l in d u st r y w a s p ou r ed in t o t h e sea t o en t er t h e h u m a n food ch a in t h r ou gh con t a m in a t ed sea food . T h e r esu lt w a s t h e on s et of d eb ilit a t in g h u m a n illn es s es a s s ocia t ed w it h m er cu r y p oison in g.
Chemicals
T h er e a r e cer t a in a r ea s of en v ir on m en t a l d e gr a d a t ion t h a t a lt h ou gh t a k in g p la ce w it h in n a t ion a l b ou n d a r ies a r e s o
w id es p r ea d a s t o ju s t ify glob a l con cer n . On e su ch a r ea is ch em ica l p ollu t ion . F r om t im e im m em or ia l, m a n h a s en ga ged in t h e m a n u -fa ct u r e of ch em ica ls. T h ese p r od u ct s a r e u sed on ou r b od ies, in ou r h om es, fi eld s, food , t r a n s p or t a n d in d eed in a lm os t ever y a s p ect of ou r life. It h a s b een ca lcu la t ed t h a t b et w een 1956 a n d 1982, over 4 m illion d ist in ct ch em ica l com p ou n d s w er e for m u la t ed w it h a s m a n y a s 6,000 n ew for m u la t ion s b ein g cr ea t ed w eek ly sin ce. Wils on (1993) s t a t es t h a t a p p r oxim a t ely 3,000 ch em ica ls a r e d elib er a t ely a d d ed t o food , 700 h ave b een fou n d in d r in k in g w a t er, a b ou t 400 h ave b een id en t ifi ed in h u m a n t is-su es a n d over 500 cou ld b e fou n d u n d er t h e k it ch en s in k or in t h e la u n d r y r oom of t h e aver a ge h ou se. T h e fa ct t h a t over 70,000 ch em ica ls a r e in d a ily u se cr ea t es a ca u s e for con -cer n es p ecia lly w it h r e ga r d t o iss u es of h ea lt h a n d s a fet y (p. 1).
P es t icid es a r e p r ob a bly t h e m ost
w id es p r ea d a n d in fa m ou s sou r ce of ch em ica l con t a m in a t ion w h ich exist s in t h e a t m os-p h er e, w a t er, soil a n d food . T h e wor ld wok e u p t o t h e h or r or s of t h e in d iscr im in a t e u se of p est icid es w it h t h e p u blica t ion of t h e fa m ou s S ilen t S p r in g by Ra ch el Ca r son (1991). T h e w id es p r ea d u se of p es t icid es is a fea t u r e of t h e t w en t iet h cen t u r y, t h e m a n ifest a t ion of a n ot h er t ool t o a sser t con t r ol over n a t u r e. T h e r ise of p es t icid es is in t im a t ely lin k ed w it h t h e d iscover y in 1939 of t h e in sect icid a l ca p a b ilit ies of d ich lor d ip h en y l-t r ich lor o-et h a n e (DDT) (McE w en a n d St e p h en son , 1979 p p. 2-4). F r om t h a t p oin t on w a r d s p est icid es h ave p layed a n im p or t a n t r ole in h u m a n societ y. T h ey h ave b een u s ed for a m y r ia d ca u ses, su ch a s t h e con t r ollin g of p est s, en h a n cem en t of cr op s, d est r u ct ion of d isea ca u sin g in sect s a n d im p r ovem en t of h ou se-h old con d it ion s by er a d ica t in g t se-h ose liv in g or ga n ism s t h a t h ave led t o d iscom for t in dw ellin g p la ces (McE w en a n d St e p h en son , 1979, p p. 8-19).
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In t h e m a jor it y of ca ses exp osu r e is v ia in h a la t ion bu t it ca n a lso r es u lt fr om exp o-s u r e of t h e o-s k in (Lip p m a n n a n d Sch leo-s in ger, 1979, p. 51). T h e r es p ir a t or y t r a ct is t h e m a in p oin t of en t r y in t o h u m a n s for a ir b or n e ch em ica ls. Ch em ica ls w h ich a r e w a t er b or n e or t r a n s p or t ed in food r ea ch m a n t h r ou gh t h e ga s t r oin t es t in a l t r a ct . T h ese ca n a ls o b e a b s or b ed in t o t h e h u m a n b ody t h r ou gh t h e s k in . T h e r a n ge of b iologica l r es p on s es t o ch em ica l con t a m in a n t s in t h e b ody is q u it e d iver s e a n d m ay r a n ge fr om ir r it a n t , fi b r ot ic, a s p h y xia n t , a ller gic t o ca r cin ogen ic (Lip p -m a n n a n d Sch les in ger, 1979, p p. 194-214). It h a s b een es t im a t ed t h a t t h r ee ou t of ever y t en p eop le in t h e USA ca n exp ect t o con t r a ct s om e for m of ca n cer, a n d in a p p r oxim a t ely 98 p er cen t of t h e ca ses t h es e m ay b e lin k ed t o ch em ica l exp osu r e. In a d d it ion t o ca n cer, ch em ica l exp osu r e is r es p on s ible for a m y r ia d ot h er h ea lt h p r oblem s r a n gin g fr om n eu -r ologica l, im m u n ologica l a n d d evelop m en t a l t o r e p r od u ct ion (Wils on , 1993, p p. 2-4). Wils on p r ov id es on e of t h e m os t com p r eh en sive t r ea -t ises on -t h e h ea l-t h im p lica -t ion s of va r iou s ch em ica ls. T h e list of h u n d r ed s of lik ely a il-m en t s fr oil-m ch eil-m ica l exp osu r e is a ch illin g r em in d er of h u m a n v u ln er a b ilit y (Wils on , 1993, p p. 11-72). Wit h ou t d ou b t , exp os u r e t o h a r m fu l ch em ica ls ca n in cr ea se m or t a lit y a n d m or b id it y (Bla in , 1990). M ost ca s es of w id es p r ea d m or t a lit y a r e t h e r es u lt of in d u s -t r ia l a ccid en -t s a n d s p illa ge of ch em ica ls a s occu r r ed in Bh op a l, in In d ia . H ow ever, a lt h ou gh d ea t h s h ave occu r r ed t h r ou gh les s s p ect a cu la r m ed ia , t h er e a r e m u ch few er d a t a ava ila ble in ca ses w h er e t h e exp os u r e m ay h ave b een a lon g-t er m p r oblem (Lip p m a n n a n d Sch les in ger, 1979, p p. 53-4).
T h e occu p a t ion a l en v ir on m en t is a n ot h er m a jor sou r ce of exp os u r e t o h a r m fu l ch em ica ls a m on g h u m a n s a n d m er it s s p ecia l m en -t ion . I-t h a s b een a s ser -t ed -t h a -t m os -t ca ses of ch em ica l p oison in g h ave a r is en fr om occu p a -t ion a l exp os u r e. Mor e -t h a n ever, ch em ica l p r od u ct ion is s h ift in g t o d evelop in g cou n t r ies w h er e t h e r e gu la t or y fr a m ewor k is less s ever e t h a n in d evelop ed cou n t r ies. T h e r esu lt h a s b een a r ise in ca s es of ch em ica l p ois on in g a lt h ou gh t h er e is sign ifi ca n t u n d er -r e p o-r t in g a n d la ck of -r es ea -r ch in t h is a -r ea . Va r iou s s t u d ies, h ow ever, h ave led t o r ea son a ble es t im a t es of t h e m a gn it u d e of t h e p r ob lem . In Ta iw a n it w a s d is cover ed t h a t em p loy -ees in a p la n t en ga ged in t h e m a n u fa ct u r e of p est icid es h a d s u b st a n t ia lly d ecr ea sed p la s m a ch olin est er a se (Wu , 1989, p p. 661-3). N ot on ly t h os e w h o m a n u fa ct u r e t h e p est i-cid es a r e a ffect ed bu t wor k er s w h o a r e en ga ged in a d m in is t er in g t h e ch em ica ls a r e eq u a lly, if n ot m or e, a t r isk . A s t u dy in In d ia r evea led a p r eva len ce of r es p ir a t or y a ilm en t s a m on g s p r ayer s in m a n go p la n t a t ion s. T h e
sp r ayer s, b eca u se of a n a b sen ce of p r op er sa fet y eq u ip m en t , w er e d ir ect ly exp osed t o t h e p est icid es t h r ou gh sk in con t a ct a n d r esp ir a t ion a n d in d iir ect ly t h ir ou gh food con su m p -t ion (Ra s-t ogi, 1989). T h e p r oblem of im p r op er p r ot ect ion of wor k er s u sin g p es t icid es h a s given r ise t o w h a t h a s b een d escr ib ed a s a n e p id em ic of p est icid e p oison in g in N ica r a gu a (McCon n ell a n d H r u s k a , 1993).
T h e exa m p les n ot ed a b ove in t h e ca se of wor k er s d ea lin g w it h h a r m fu l ch em ica ls a r e n ot is ola t ed bu t in d ica t ive of a m u ch b r oa d er p r oblem a n d p es t icid e p oison in g h a s em er ged a s a m a jor con cer n . WH O a n d UN E P h ave est im a t ed t h a t over on e m illion ca ses of p est i-cid e p oison in g occu r yea r ly, w it h a r ou n d 20,000 fa t a lit ies (P im en t el et a l., 1992, p. 750). A m or e r ecen t st u dy h a s su ggest ed t h a t t h e in cid en t s of p es t icid e p oison in g m ay b e a s h igh a s t h r ee m illion a n n u a lly (McCon n ell a n d H r u sk a , 1993, p. 1559). In s p it e of t h e d evelop ed cou n t r ies u sin g a r ou n d 80 p er cen t of t h e p est icid es p r od u ced in t h e wor ld , it h a s b een es t im a t ed t h a t 99 p er cen t of p est icid e fa t a lit ies occu r in t h e d evelop in g wor ld , w it h ju st a s sign ifi ca n t a p er cen t a ge in t h e a r ea of n on fa t a l p oison in gs. An ot h er a r ea of con -cer n in t h e d evelop in g wor ld is t h e h igh level of p er in a t a l m or t a lit y. It h a s b een est im a t ed t h a t t h er e a r e a b ou t s even m illion p er in a t a l d ea t h s p er a n n u m in d evelop in g cou n t r ies. A s t u dy in Su d a n h a s in d ica t ed a con sist en t a n d s t a t is t ica lly sign ifi ca n t r ela t ion sh ip b et w een exp osu r e t o p est icid es a n d t h e in cr ea sed r isk of st ill b ir t h or p er in a t a l d ea t h (Ta h a a n d Gr ay, 1993, p p. 319-20).
Nuclear operations
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en vir on m en t ca n a lso fi n d its w ay in to th e h u m a n body eith er by dr in k in g a ffected w a ter or con su m ption of fi sh a n d oth er a qu a tic sou r ces of h u m a n food th a t m ay h ave been con ta m in a ted (Pen tr ea th , 1980, pp. 158-65).
A d a n ger ou s t h r ea t t o h u m a n h ea lt h a r is-in g fr om t h e u se of n u clea r t ech n ology is t h e p os s ib ilit y of exp os u r e t o r a d ia t ion . In ju r y t o liv in g or ga n ism s a r is es fr om d a m a ge t o cells in t h e b ody. H igh levels of r a d ia t ion lea d t o b ot h som a t ic a n d gen et ic ch a n ges in liv in g or ga n ism s. Som a t ic effect s a r e t h ose r es u lt -in g d ir ect ly fr om t h e r a d ia t ion d os e r eceived by t h e a ffect ed cells a n d m a n ifest t h em s elves in s om e for m of r a d ia t ion -in d u ced m a lig-n a lig-n cy (E ich h olz, 1977, p. 121). T h e effect s in clu d e in cr ea sed in cid en ce of leu k a em ia a n d ot h er t y p es of ca n cer, in clu d in g t u m ou r s of t h e t h y r oid gla n d , lu n g, a n d t h e b r ea st in wom en . H igh er in cid en ce of b on e ca n cer h a s a lso b een ob s er ved in som e in st a n ces (Gla s -st on e a n d J or d a n , 1980, p p. 184-91). Gen et ic effect s a r is e w h en t h e r e p r od u ct ive cells a r e ir r a d ia t ed , r esu lt in g in ch a n ges in t h e gen es or ch r om os om es of t h ese cells, a n d t h e su b s e-q u en t h a n d in g d ow n of t h ese ch a n ges t o d escen d a n t s of t h e a ffect ed in d iv id u a l. T h er e a r e d iffer en t t y p es of gen et ic ch a n ges, n a m ely, gen e m u t a t ion s, ch r om osom e a b er r a -t ion s, a n d ch a n ges in -t h e n u m b er of ch r om osom es. T h ese ch a n ges ca n r es u lt in t h e p r es -en ce of a b n or m a lit ies in offsp r in g r a n gin g fr om let h a l t o m ild ly d et r im en t a l (E ich h olz, 1977, p. 123).
Environmental degradation and
human health: the regional
connection
Freshwater
Wa t er is t h e ess en ce of life, w it h ou t w h ich m a n ’s exist en ce ca n b e t r a n sfor m ed in t o on e con t in u ou s lit u r gy of s u ffer in g. T h is is cu r -r en t ly ev id en t in p la ces lik e t h e Sa h el -r e gion . H ow ever, in a d d it ion t o w a t er ava ila b ilit y, w a t er q u a lit y a ls o p oses a p r oblem , p a r t icu la r ly in d evelop in g cou n t r ies. It m ay b e a ccu -r a t e t o s t a t e t h a t t h e n eed fo-r a s a fe d om es t ic w a t er s u p p ly is p er h a p s t h e gr ea t es t t h r ea t t o t h e d evelop in g wor ld (Wit t , 1982, p. 301). Wh er e w a t er s u p p ly is low a n d w a t er t r ea t -m en t in efficien t , h u -m a n h ea lt h is a t it s -m ost v u ln er a ble p oin t (Fea ch em , 1983). T h e con -cer n in m a n y d evelop in g cou n t r ies focu ses on a s u p p ly of s a fe a n d a d eq u a t e a m ou n t s of w a t er for con su m p t ion a n d sa n it a r y p u r p os es. T h e Un it ed N a t ion s Develop m en t P r ogr a m m e (UN DP ) h a s est im a t ed t h a t d u r in g t h e p er iod 1988-1991, 70 p er cen t of t h e d evelop in g wor ld h a d a ccess t o s a fe w a t er, w it h t h e fi gu r e d r op p in g t o 45 p er cen t for t h e lea s t d evelop ed cou n t r ies. Wit h r es p ect t o
sa n it a t ion fa cilit ies, 56 p er cen t h a d a ccess w it h a m er e 32 p er cen t for t h e lea st d evelop ed cou n t r ies (UN DP, 1994, Ta ble 2, p. 132). T h ese fi gu r es t r a n sla t ed in 1992 t o a p p r oxim a t ely 1.3 b illion p eop le w it h ou t a ccess t o sa fe w a t er a n d 1.9 b illion w it h ou t a ccess t o p r op er sa n i-t a i-t ion fa cilii-t ies (UN DP, 1994, Ta ble 3, p. 135).
T h e h ea lt h im p lica t ion s fl ow in g fr om t h e fa ilu r e t o s u p p ly w a t er of su fficien t q u a lit y for d om est ic u sa ge a r e t r em en d ou s in d evel-op in g cou n t r ies. In a d d it ion t o t h e d ir ect t h r ea t s t h a t m ay fl ow fr om con s u m p t ion of w a t er con t a m in a t ed by p ollu t a n t s su ch a s ch em ica l a gen t s, t h e gr ea t est ca u se of m or t a l-it y a n d m or b id l-it y is t h e s p r ea d of in fect iou s d isea ses. In t h e d evelop in g wor ld t h ese a ccou n t for 72 p er cen t of t h e d ea t h s of a ll ch ild r en u n d er fi ve yea r s old a n d 45 p er cen t of d ea t h s over a ll. T h e p r eva len ce of in fec-t iou s d isea s es is d ir ecfec-t ly a fec-t fec-t r ibu fec-t a ble fec-t o m a l-n u t r it iol-n , il-n a d eq u a t e w a t er su p p ly, la ck of sa n it a t ion fa cilit ies, p oor h ygien ic p r a ct ices a n d u n sa t isfa ct or y liv in g con d it ion s (UN E P, 1993, p. 235).
T h er e a r e fi ve m a jor p a t h w ay s for w a t er -r ela t ed d is ea ses t o b e t -r a n sm it t ed t o h u m a n s. F ir st , t h er e a r e w a t er -b or n e d isea s es w h ich ca n a r ise fr om m u lt ip le ca u s es, su ch a s t h e p r esen ce of h u m a n or a n im a l fa eces in w a t er, u r in e in fect ed by b a ct er ia a n d p a t h ogen ic v ir u s es. T h ese or ga n ism s a r e t r a n sm it t ed t o h u m a n s w h en t h e w a t er is u sed for d r in k in g or food p r e p a r a t ion (UN E P, 1993, p. 235). E xa m p les of w a t er -b or n e d isea ses a r e p oliom yelit is, a sca r ia s is, en t er ic fever a n d d ia r r h oea l d is ea ses. In t h e la t e 1980s t h er e w er e a p p r oxim a t ely t h r ee b illion ca ses of t h ese d isea s es, p r im a r ily in t h e d evelop in g wor ld w it h over 4.07 m illion fa t a lit ies, w it h d ia r r h oea l d is ea ses su ch a s ch oler a a n d t y p h oid a ccou n t in g for fou r m illion d ea t h s (UN E P, 1993, Ta ble 5.6, p. 256).
Wa t er -w a sh ed d isea ses a r e ca u s ed by t h e sca r cit y of w a t er, w h ich r en d er s clea n lin ess d ifficu lt t o a t t a in . T h is ca t e gor y in clu d es a ll w a t er b or n e d isea ses in a d d it ion t o in fest a -t ion w i-t h lice or m i-t es w h ich a r e vec-t or s of t y p h u s (N a s h , 1993, p. 26). Com m on t y p es of w a t er -w a sh ed a fflict ion s a r e t r a ch om a a n d leish m a n ia sis. In t h e la t e 1980s t h ese con d i-t ion s a ffeci-t ed u p i-t o 21 m illion p eop le in i-t h e d evelop in g wor ld a n d in t h e ca se of t r a ch om a r en d er ed b et w een six a n d n in e m illion p eop le blin d (UN E P, 1993, Ta ble 5.6, p. 256).
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210 m illion p eop le in t h e d evelop in g wor ld in t h e la t e 1980s. Du r in g t h is p er iod , sch is t os o-m ia sis r es u lt ed in a p p r oxio-m a t ely 200, 000 fa t a lit ies (UN E P, 1993, Ta ble 5.6, p. 256).
Wa t er -r ela t ed d isea ses a r e t h ose in w h ich in s ect vect or s of p a r a sit ic d isea ses r ely on w a t er a s a h a b it a t . In t h is ca s e t r a n sm iss ion is n ot d u e t o d ir ect h u m a n con t a ct w it h w a t er (UN E P, 1993, p. 235). Afr ica n t r y p a n os om ia sis, ele p h a n t ia sis, on ch ocer cia s is, yellow fever, d en gu e fever, J a p a n ese en ce p h a lit is a n d m a la r ia d om in a t e t h is a r ea a ccou n t in g for 435.04 m illion ca s es in t h e d evelop in g wor ld in t h e 1980s w it h fa t a lit ies r a n gin g b et w een on e a n d 2.05 m illion . M a la r ia a ccou n t ed for t h e bu lk of t h e ca ses w it h 267 m illion a n d b et w een on e a n d t wo m illion of t h e r ecor d ed d ea t h s (UN E P, 1993, Ta ble 5.6, p. 256).
F in a lly, t h er e a r e w a t er -d is p er sed in fec-t ion s w h er e fec-t h e in fecfec-t iou s a gen fec-t s fec-t h r ive in fr es h w a t er a n d a r e in h a led in t o t h e r es p ir a -t or y -t r a c-t w i-t h m in u -t e w a -t er d r op le-t s. L egion ella is a n exa m p le of a w a t er -d is p er sed in fect ion a n d t h is ca t e gor y of w a t er -r ela t ed d is ea s es is t h e on ly on e t h a t a p p ea r s w it h s om e fr eq u en cy in d evelop ed cou n t r ies (UN E P, 1993, p. 235).
T h e st a r t lin g st a t is t ics of w a t er b a s ed d is -ea s es r ecit ed a b ove a r e p er h a p s t h e t r a gic p r oof t h a t t h e gr ea t es t t h r ea t t o d evelop in g cou n t r ies lies in ob t a in in g a fr es h w a t er s u p p ly for d om es t ic u s a ge. Wit h ou t u r gen t a t t en -t ion -t o -t h is r eq u ir em en -t , -t h e lives of b illion s m ay b e s im p ly w a st ed aw ay.
Desertification
On e of t h e a la r m in g fea t u r es of t h e la s t t wo d eca d es h a s b een t h e gr ow in g d es er t ifi ca t ion of s ever a l r e gion s in t h e d evelop in g wor ld , t h e m os t n ot icea ble b ein g t h e Su b -Sa h a r a n r e gion . Wh ile t h e los s of b iologica l d iver s it y a n d h u m a n s u ffer in g a r e t h e m os t a p p a r en t m a n ifes t a t ion s of d eser t ifi ca t ion , t h er e m ay even b e h ea lt h con s eq u en ces. Cr op fa ilu r e a n d los s of livest ock oft en lea d s t o m a ln u t r i-t ion . Wea k en ed b od ies a r e i-t h en r en d er ed s u sce p t ible t o t h e r ava ges of h u n ger a n d d is-ea s e. Alt h ou gh few d isis-ea ses a r e s p ecifi c t o d es er t ifi ca t ion , eye d isea s e su ch a s t r a ch om a a n d ot h er a fflict ion s lik e b ilh a r zia m ay b e m or e p r om in en t u n d er con d it ion s of d eser t i-fi ca t ion (Secr et a r ia t of t h e Un it ed N a t ion s Con fer en ce on Deser t ifi ca t ion , 1977, p. 42).
Environmental degradation and
human health: national risk
Indoor air pollution
T h er e a r e a r ea s of en v ir on m en t a l a bu s e t h a t give r is e p r ed om in a n t ly t o n a t ion a l h ea lt h p r oblem s. On e su ch a r ea is in d oor a ir p ollu -t ion w h ich h a s r ava ged -t h e d evelop in g wor ld
w it h a n es t im a t ed 400 t o 700 m illion p eop le b ein g a t r isk a n d a n n u a l d ea t h s t o in fa n t s a n d ch ild r en of a r ou n d fou r m illion a n n u a lly (Wor ld Ba n k , 1992, p. 52). T h e m a jor p r oblem s a r e ca u sed by n on b iom a ss a n d b iom a ss com -bu st ion . N on -b iom a ss in d oor com -bu st ion n or m a lly p er t a in s t o t h e u se of ga s r a n ges for cook in g. Gen er a lly, in d oor ga s r a n ges d o n ot h ave a ga s exh a u st sy st em , so a llow in g t h e ga s eou s p r od u ct s of com bu st ion t o en t er t h e in d oor a ir d ir ect ly d u r in g u se (Gr eim , 1989, p. 193). T h e t wo m a jor em ission s a r e ca r b on m on oxid e a n d n it r ogen d ioxid e.
Ca r b on m on oxid e is em it t ed a s a r esu lt of t h e in com p let e com bu st ion of ca r b on a ceou s m a t er ia l. In a d d it ion t o ga s r a n ges, w a t er h ea t er s a n d ga s or coa l h ea t er s a r e m a jor in d oor sou r ces of ca r b on m on oxid e. Ca r b on m on oxid e p r od u ces t oxic effect s in t h e h u m a n b ody. Du e t o it s a ffin it y t o h a em oglob in it d isp la ces oxygen , so low er in g t h e oxy -gen ca r r y in g ca p a cit y of blood . Ca r b on m on oxid e h a s it s m os t t oxic a cu t e effect s on t h e or ga n s w it h h igh oxygen r eq u ir em en t s, su ch a s t h e h ea r t a n d t h e b r a in . At low levels, ca r b on m on oxid e ca n ca u se fl u lik e sy m p -t om s es p ecia lly in ch ild r en (Gold , 1992, p p. 216-7). At h igh levels, it ca n lea d t o com a a n d p ossibly d ea t h (Wellbu r n , 1988, p. 17). N it r o-gen d ioxid e is a n oxid a n t t h a t is solu ble in t issu es. Most in h a led n it r ogen d ioxid e is r et a in ed in t h e lu n gs a n d d e p osit ed p r im a r ily in t h e la r ge a n d sm a ll a ir w ay s. At h igh con -cen t r a t ion s n it r ogen d ioxid e ca u ses ext en sive lu n g in ju r ies. F a t a l p u lm on a r y oed em a a n d b r on ch op n eu m on ia h ave b een r e p or t ed a t h igh con cen t r a t ion s, w it h b r on ch it is a n d p n eu m on ia a t low er levels (La m b er t a n d Sa m et , 1994, p. 612).
Biom a ss fu els com p r ise p r ocessed b iom a ss su ch a s ch a r coa l, m et h a n e, loggin g w a st e a n d saw d u st . Un p r ocessed b iom a s s fu els a r e gen -er a t ed fr om sou r ces su ch a s wood , d u n g, st r aw, a gr icu lt u r a l w a st es a n d ve get a ble m a t t er. Bu r n in g of b iom a ss for fu el ca n r esu lt in t h e p r od u ct ion of p a r t icu la t es,
b en zo(a )py r en e, ca r b on m on oxid e, n it r ogen d ioxid e, su lp h u r d ioxid e, for m a ld eh yd e, vola t ile or ga n ic com p ou n d s a n d n u m er ou s ot h er su b st a n ces (Gold , 1992, p. 218). In t h is a r ea t h e d evelop in g wor ld a p p ea r s m ost v u l-n er a ble. Ul-n for t u l-n a t ely, exce p t for t h e wor k of Ch en (1990), t h e is su e h a s n ot b een com p r e-h en sively r esea r ce-h ed in t e-h e d evelop in g wor ld .
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cou n tr ies, biom a ss a ccou n ts for a s m u ch a s 90 per cen t of th e pr im a r y en er gy. Appr oxim a tely 50 per cen t of th e wor ld’s popu la tion pr edom i-n a i-n tly fr om th e developii-n g wor ld, r ely m a ii-n ly or exclu sively on biom a ss fu els to sa tisfy th eir da ily en er gy n eeds, th a t is, for cook in g a n d h ea tin g (UN E P, 1993, p. 273).
In d evelop in g cou n t r ies, it h a s b een sh ow n t h a t t h e in cid en ce of lu n g ca n cer r is es a s a r esu lt of exp os u r e t o p a r t icu la t es a n d ga s eou s em iss ion a r is in g fr om bu r n in g of b iom a s s fu el in w h a t a r e oft en p oor ly ven t ila t ed h ou ses. Ad d it ion a lly, t h er e is a h igh er in ci-d en ce of ch r on ic b r on ch it is in n on -s m ok in g wom en , a n d r es p ir a t or y a ilm en t s a n d p n eu -m on ia a -m on g ch ild r en (Gold , 1992, p. 218). T h es e t r en d s h ave b een b or n e ou t in t h e in cr ea s in g n u m b er of ca s e s t u d ies p er for m ed in d evelop in g cou n t r ies, p a r t icu la r ly in Afr ica a n d As ia . E xp osu r e t o ga s eou s em is-sion s fr om b iom a s s bu r n in g h a s b een lin k ed w it h d im in ish ed lu n g fu n ct ion s in ch ild r en in Ku a la Lu m p u r, Ma lay sia (Azizi a n d H en r y, 1990, p. 26). In a ca s e con t r ol s t u dy p er for m ed in t h e p r ov in ce of Gu a n gzh ou , Ch in a , lu n g ca n cer em er ged a s t h e m a jor ca u s e of d ea t h by ca n cer a m on g m en a n d wom en . Sm ok in g a p p ea r ed t o b e d om in a n t a m on g m a le fa t a li-t ies bu li-t w ili-t h r es p ecli-t li-t o wom en cou ld n oli-t h ave b een a sign ifi ca n t fa ct or, b eca u se of low er sm ok in g a ct iv it ies. T h e r es u lt s of t h e s t u dy in d ica t ed t h a t in d oor a ir p ollu t ion d u e t o h om e cook in g w a s t h e d r iv in g fa ct or in lu n g ca n cer a m on g wom en w h o w er e exp os ed t o coa l fu m es a n d cook in g oil va p ou r s (Liu et a l., 1993). In Sh en ya n g, Ch in a , a ca se con t r ol s t u dy of 1,249 p a t ien t s w it h lu n g ca n cer fou n d t h a t w h ile ciga r et t e sm ok in g w a s a m a jor con t r ibu t or y fa ct or, in d oor a ir p ollu t ion w a s t h e s ign ifi ca n t fa ct or in t h e ca s e of wom en . T h e r is k of lu n g ca n cer w a s b et w een 50 t o 70 p er cen t h igh er in h om es h ea t ed by coa ls or u sin g coa ls for cook in g. Wh er e k a n g w a s u sed for h ea t in g b ed r oom s or cook in g w a s d on e w it h in clos e p r oxim it y of s lee p in g q u a r t er s, t h e r is k w a s a t it s h igh es t level (Xu , 1989). In Sh a n gh a i, t h e in d oor bu r n in g of coa l h a s b een p os it ively lin k ed t o a h igh er in cid en ce of s t r ok e a m on g m a les (Zh a n g, 1988, p. 976).
T h e gr im p ict u r e in As ia ext en d s t o Afr ica w h er e s im ila r r es u lt s w er e ob t a in ed . In Zim -b a -bw e, in ves t iga t ion s h ave r evea led t h a t ch ild r en a r e m or e lik ely t o s u ffer fr om p n eu -m on ia in h o-m es w h er e wood is u sed a s fu el (L a n cet, 1992, p. 397). In r u r a l Ken ya , m ea s u r e-m en t s of in d oor a ir p ollu t ion r evea led t h a t r esp ir a ble p a r t icu la t es a n d n it r ogen oxid e w er e a p p r oxim a t ely t en t im es h igh er t h a n t h e r ecom m en d ed a ir q u a lit y gu id elin es. Ad d i-t ion a lly, i-t h e level of p olycyclic a r om a i-t ic h yd r oca r b on s w a s a ls o q u it e h igh (Boleij et a l., 1989, p. 1677). A s t u dy in Gh a n a h a s n ot ed t h e a dver se h ea lt h effect s on wom en a n d
you n g ch ild r en a r isin g fr om t h e bu r n in g of b iom a ss fu el for cook in g. A p let h or a of r esp i-r a t oi-r y p i-r oblem s b ea i-r s w it n ess t o t h e t i-r a gedy of in d oor a ir p ollu t ion (McGr a n a h a n a n d Son gsor e, 1994, p p. 4-45).
P a n d ey et a l. (1989) h ave n ot ed t h a t , in t h e d evelop in g wor ld , t h e exp osu r e t o h igh levels of sm ok e fr om in d oor b iom a s s bu r n in g w it h ou t a fl u e or ch im n ey a n d w it h p oor ven t ila -t ion is r esp on sible for a cu -t e r es p ir a -t or y in fec-t ion s fec-t h a fec-t ca u se on e-fec-t h ir d of a ll ch ild h ood d ea t h s u n d er fi ve yea r s. F u r t h er, t h e b a sic ev id en ce su ggest s t h a t p ea k a n d d a ily exp o-su r es t o in d oor p a r t icu la t e levels wou ld a p p ea r a t t im es t o b e 20 t im es gr ea t er in t h e d evelop in g wor ld t h a n t h e d evelop ed (P a n d ey et a l., 1989, p. 427). On e st u dy h a s r evea led t h a t in s elect ed d evelop in g cou n t r ies, t h e aver a ge a n n u a l m icr ogr a m s of p ollu t a n t is 300 p er cu b ic m et r e of a ir in r u r a l a r ea s, w it h t h e cor r es p on d in g fi gu r e for t h e d evelop ed wor ld b ein g 75 p er cu b ic m et r e of a ir (Sm it h , 1988, p. 19).
Outdoor air pollution
Ou t d oor a ir p ollu t ion is a n ot h er ser iou s en v i-r on m en t a l fa ct oi-r t h a t ca n im p a ct a dvei-r sely on h u m a n h ea lt h . Alt h ou gh it is d ea lt w it h a s a n a t ion a l p r oblem , it ca n q u it e ea sily p ose t r a n sb ou n d a r y p r oblem s, esp ecia lly in a r ea s of con cen t r a t ed a ir p ollu t ion , su ch a s t h e Bla ck T r ia n gle in E u r op e b et w een Ger m a n y, P ola n d a n d t h e Czech Re p u blic. In d eed , it is a r gu a ble t h a t ou t d oor a ir p ollu t ion a m on g n a t ion s w it h com m on b ou n d a r ies is so w id e-sp r ea d a s t o ju st ify it s con s id er a t ion a s a n a r ea of glob a l con cer n . T h er e a r e m a n y for m s of ou t d oor a ir p ollu t ion a n d t h is p a p er w ill focu s on ju st a few exa m p les. On e com m on t y p e of ou t d oor a ir p ollu t a n t is r efer r ed t o a s su sp en d ed p a r t icu la t e m a t t er (SP M). SP M r efer s t o t h e w id e r a n ge of fi n ely d iv id ed solid s or liq u id s d isp er sed in t o t h e a t m os-p h er e fr om n a t u r a l sou r ces, in d u s t r ia l a ct iv i-t ies a n d com bu s i-t ion p r oces ses. T h e com p osi-t ion of SP Ms va r ies bu osi-t osi-t y p ica lly in clu d es ca r b on , h igh er h yd r oca r b on s for m ed by in com p let e com bu st ion of h yd r oca r b on fu els, a n d s u lp h u r, t h e la t t er of w h ich m ay a ccou n t for u p t o a p p r oxim a t ely 20 p er cen t of t h e t ot a l SP Ms (E lsom , 1992, p. 21). T h u s, t h e effect s of SP Ms on t h e en v ir on m en t a r e h igh ly in fl u -en ced by su lp h u r -b a sed em ission s. T h e h ea lt h im p a ct of su ch levels of em ission s is t r em en d ou s a n d exp osu r e t o SP Ms h a s b een lin k ed w it h h igh er in cid en ce of a st h m a , b r on -ch it is a n d p u lm on a r y em p h y s em a (E lsom , 1992, p. 27).
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or p h ot och em ica lly w it h ot h er p ollu t a n t s t o for m s u lp h u r t r ioxid e, s u lp h u r ic a cid a n d s u lp h a t es (E ls om , 1992, p. 22). Su lp h u r is h is -t or ica lly r e ga r d ed a s on e of -t h e -t r a d i-t ion a l s ou r ces of p ollu t ion . At it s zen it h , s u lp h u r p ollu t ion h a s m a n ifest ed it s elf in t h e fa m ou s s u lp h u r ou s sm ogs t h a t a fflict ed m os t in d u s -t r ia l ci-t ies. Sm ogs a r e gen er a lly for m ed w h en m et eor ologica l con d it ion s fa il t o d isp er s e la r ge q u a n t it ies of p ollu t a n t s em it t ed fr om in d u s t r y, veh icles a n d d om es t ic sou r ces. Su l-p h u r -r ela t ed l-p r od u ct s ca n h ave a fa t a l im l-p a ct on h u m a n h ea lt h a s ev id en ced by t h e in fa -m ou s s u lp h u r ou s s -m og t h a t st r u ck Lon d on in Decem b er 1952. T h e d ea t h of n ea r ly 4, 000 p eop le w a s t h e r es u lt w it h t h e la r ges t con t r ib u t or b ein g b r on ch it is, follow ed by ot h er d is -ea s es ch a r a ct er ized by im p a ir m en t of r es p i-r a t oi-r y fu n ct ion s (E ls om , 1992, p p. 22-5). On a less fa t a l b a s is, s u lp h u r d ioxid e p r od u ces a s t r on g ir r it a t ion on t h e eyes a n d t h e n a s a l p a ss a gew ay. Mor eover, su lp h u r d ioxid e em is-s ion is-s h ave b een lin k ed w it h h igh er
in cid en ces of a s t h m a , b r on ch it is, p u lm on a r y em p h y s em a a n d a gen er a l r ed u ct ion of lu n g fu n ct ion s esp ecia lly in ch ild r en (Wellbu r n , 1988, p p. 53-6). An ot h er p a r t icu la r va r ia t ion of s u lp h u r em is sion s is h yd r ogen su lp h id e. It is s ligh t ly p h ot ot oxic a n d a t h igh levels it ca n ir r it a t e t h e lu n g p a ssa ge a n d eyes of h u m a n s p oss ibly r es u lt in g in p n eu m on ia a n d con ju n c-t iv ic-t is (Wellbu r n , 1988, p p. 182-6).
Oxid es of n it r ogen a r e a lso d a n ger ou s s ou r ces of a ir p ollu t ion . T h e p r in cip a l a n t h r o-p ogen ic em is sion s of oxid es of n it r ogen a r e fr om t h e com bu s t ion of fos sil fu els in fi xed s ou r ces lik e p ow er p la n t s a n d h ea t in g, a n d in m ot or ca r s fr om t h e in t er n a l com bu s t ion en gin e. In d evelop ed cou n t r ies, t h e op er a t ion of p ow er p la n t s con t r ibu t es a p p r oxim a t ely 45 p er cen t of t h e em is sion of oxid es of n it r ogen , r oa d t r a n sp or t a b ou t 30 p er cen t , w it h t h e b a la n ce fr om d om est ic a n d gen er a l in d u st r ia l s ou r ces (Wellbu r n , 1988, p. 68). T h e h ea lt h im p lica t ion s of em is sion of oxid es of n it r ogen m ay n ot b e a s p ow er fu l a s ot h er a ir p ollu t a n t s bu t ou gh t n ot t o b e u n d er es t im a t ed . N it r ogen d ioxid e is k n ow n for it s s t in gin g, su ffoca t in g od ou r. F u r t h er, ev id en ce p oin t s t o in cr ea sed a ir w ay r es is t a n ce a n d s en sit iv it y t o b r on -ch ocon s t r ict or s in cer t a in in d iv id u a ls (E lsom , 1992, p. 49). At h igh levels of exp os u r e, n it r ou s fu m es m ay ca u s e cou gh in g,
h ea d a ch es a n d ch est t igh t n es s. T h is m ay lea d t o su d d en cir cu la t or y colla p se a n d w a t er a ccu m u la t ion in t h e lu n gs. E xces s blood n it r a t e m ay r ed u ce blood p r es s u r e w h ich in t u r n cou ld ca u se d est r u ct ion of blood cells, liver a n d k id n ey d efect s (Wellbu r n , 1988, p. 91).
P h ot och em ica l oxid a n t s a ls o con t r ibu t e t o t h e d a n ger ou s cock t a il of a ir p ollu t a n t s t h a t a r e p r es en t t od ay. E va p or a t ion of s olven t s a n d
fu els t oget h er w it h t h e in com p let e com bu st ion of fos sil fu els ca u s es va r iou s h yd r oca r -b on s t o -b e r elea sed in t o t h e a t m osp h er e (Well-bu r n , 1988, p. 135). P h ot och em ica l oxid a n t s a r e s econ d a r y p ollu t a n t s for m ed by t h e a ct ion of su n ligh t on a n a t m os p h er e con t a in -in g r ea ct ive h yd r oca r b on s a n d oxid es of n it r ogen . T h es e r ea ct ion s p r od u ce m a n y oxid a n t s w it h p er oxya cet y l n it r a t e a n d ozon e b ein g t h e m os t sign ifi ca n t . T h e k ey t o t h e for m a t ion of ozon e is t h e p h ot oly sis of t h e n it r ogen d ioxid e m olecu le by u lt r av iolet r a d ia t ion d u r in g d ay ligh t h ou r s. P h ot och em ica l oxid a n t s in t h eir sm oglik e for m a r e ica p a -ble of ca u sin g eye a n d n ose ir r it a t ion . Du r in g e p isod es in Los An geles in Se p t em b er 1979, 55 p er cen t of t h e p eop le su r veyed com p la in ed of bu r n in g or ir r it a t ion of t h e eyes, 25 p er cen t r e p or t ed h ea d a ch es, b r ea t h in g ir r it a t ion , sor e t h r oa t s or st u ffy n oses, w h ile h osp it a ls r ecor d ed a lm ost a 50 p er cen t a d m it t a n ce r a t e in cr ea se for com p la in t s of lu n g d is ea ses su ch a s em p h y sem a a n d a st h m a (E lsom , 1992, p p. 40-43). St u d ies h ave r evea led t h a t exp osu r e t o ozon e ca n ca u se in cr ea sed a ir w ay r esist a n ce a n d d ecr ea s ed ven t ila t or y p er for m a n ce (F ish -m a n a n d Ka lish , 1990, p. 233). M or eover, it wou ld a p p ea r t h a t ozon e m ay in ju r e t h e b r on ch iola r a n d a lveola r w a lls of t h e lu n gs (F ish -m a n a n d Ka lish , 1990, pp. 215-6).
N ot t o b e ou t d on e a s a k ey con t r ibu t or t o ou t d oor a ir p ollu t ion is ca r b on m on oxid e. Ca r b on m on oxid e is a colou r les s, od ou r less ga s p r od u ced by t h e in com p let e com bu st ion of ca r b on -con t a in in g fu els. Ca r b on m on oxid e is a lso em it t ed fr om b iologica l a n d in d u st r ia l p r ocesses, t h e bu r n in g of for es t s a n d w a st e m a t t er p r od u ct s, a n d t h e a ct iv it ies of in d u st r ia l in sst a lla st ion s su ch a s p est r oleu m r efi n er -ies, s t eel m ills a n d p ow er st a t ion s. How ever, t h e m a jor sou r ce of ca r b on m on oxid e em is-sion s is t h e exh a u st of p et r ol-p ow er ed m ot or veh icles. In con t r a st , p r op er ly a d ju st ed d iesel en gin es em it ver y lit t le ca r b on m on oxid e (E ls om , 1992, p. 51). T h e h ea lt h im p a ct of ca r -b on m on oxid e h a s a lr ea dy -b een n ot ed in t h e d iscu ss ion on in d oor a ir p ollu t ion .
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ot h er t oxic elem en t s in t h a t it is em p loyed ext en sively by societ y. T h e m a jor s ou r ces of lea d a r is e fr om it s in d u s t r ia l a n d t ech n ologi-ca l u s a ge. T h e d om in a n t s ou r ce is in it s u se a s a n a n t i-k n ock a d d it ive in fu el. Lea d is a ls o p r od u ced in t h e m a k in g of b a t t er ies, s h eet a n d p ip e, ca ble s h ea t h in g, sold er, s h ot a n d p a in t (E ls om , 1992, p. 55). T h e in h a la t ion of lea d in t o t h e b ody com b in ed w it h it s d e p osi-t ion fr om oosi-t h er sou r ces cr ea osi-t es a sign ifi ca n osi-t h ea lt h r isk . T h e in ges t ion of lea d ca u ses a cu t e lea d p oison in g ch a r a ct er ized by bu r n -in g a b d om -in a l p a -in s, com a a n d h ea r t fa ilu r e. At low er levels, clin ica l sy m p t om s in clu d e t ir ed n es s, a ch in g of t h e join t s, a n a em ia a n d a b d om in a l colic (Dav ies, 1987, p. 4). At t h e low er levels of lea d in ges t ion , a sp ecia l con -cer n h a s a r is en w it h r es p ect t o ch ild r en . It wou ld a p p ea r t h a t a low level of lea d in t h e b od ies of ch ild r en ca n ca u se s u b t le n eu r ologi-ca l d a m a ge w it h ou t a n y a p p a r en t sign s of lea d en ce p h a lop a t h y (E lsom , 1992, p. 58). T h e r esu lt a p p ea r s t o b e a low er in t elligen t q u o-t ien o-t level for a ffeco-t ed ch ild r en .
Ca d m iu m is a t r a ce elem en t t h a t is w id ely d is p er s ed in t h e a t m os p h er e. An t h r op ogen ic em iss ion s a r e p r im a r ily d u e t o m in in g, sm elt in g, fos s il fu el com bu st ion a n d m et a l p r ocess -in g -in d u s t r ies (N or d b er g, 1992a , p. xi). All in d u s t r ia l p r ocess es in volv in g zin c a ls o h ave som e con n ect ion w it h ca d m iu m . In h u m a n s, ca d m iu m in t a k e ca n ca u s e lu n g d a m a ge, ga s t r oin t es t in a l d isor d er s, k id n ey d a m a ge a n d b on e d is ea s e. Som e st u d ies h ave su g-gest ed t h a t ca d m iu m is a ls o ca r cin ogen ic bu t t h is is s t ill n ot yet p r oved (N or d b er g, 1992b, p p. 7-9). M er cu r y is a n ot h er t r a ce elem en t t h a t is fa ir ly com m on in t h e a t m os p h er e. It s a n t h r op ogen ic sou r ces in clu d e s t eel p la n t s, p ow er p la n t s, b a t t er y fa ct or ies, or e s m elt er s, cer a m ic a n d cem en t fa ct or ies. E xp osu r e t o m er cu r y m ay lea d t o sign ifi ca n t d a m a ge t o h u m a n h ea lth (Sem u a n d Sin gh , 1986, pp. 141-6). Mer cu r y p oison in g ca n ca u se d ea t h in h u m a n s or a t low er levels s y m p t om s a k in t o lea d p ois on in g.
Hazardous waste
H a za r d ou s w a s t e is a lso ess en t ia lly a n a r ea of n a t ion a l con cer n , bu t ca p a ble of elicit in g glob a l con cer n . T h e on s et of in d u s t r ia liza t ion h a s led t o t h e p r od u ct ion of m a n y d iffer en t t y p es of h a za r d ou s w a s t e. T h e gr ow t h in t h e p r od u ct ion of h a za r d ou s w a s t e h a s coin cid ed w it h gr ow in g lim it s on t h e ca p a cit y of in d u st r ia lized n a st ion s st o d isp os e of st h es e u n d esir -a ble by -p r od u ct s. T h e r es u lt h -a s b een t h e d evelop m en t of a t r a n s b ou n d a r y t r a d e of h a za r d ou s w a s t e a n d in cr ea sin g glob a l con -cer n . T h e b iggest r isk a s s ocia t ed w it h h a z-a r d ou s w z-a s t e is it s im p r op er d isp os z-a l. N ot on ly la n d fi ll ga ses, bu t m a n y h a za r d ou s m a t e-r ia ls a e-r e ca e-r cin ogen ic oe-r n eu e-r ot oxic, a n d
p eop le w h o wor k a t t h es e d isp osa l sit es or t h ose w h o scaven ge for a liv in g m ay b e a t ser iou s r is k . T h e food ch a in wou ld a lso b e en d a n ger ed a s ca r eless d isp osa l of h a za r d ou s w a st e con t a m in a t es fl or a a n d fa u n a . N ot on ly m ay sen sit ive s p ecies d ie bu t h u m a n s m ay b ecom e in fect ed by con s u m in g con t a m in a t ed food p r od u ct s (Don a ld , 1992, p p. 422-3).
Am on g Afr ica n cou n t r ies, t h e p ot en t ia l for en v ir on m en t a l h a r m is gr ea t er b eca u se of t h e h igh u sa ge of w a t er fr om u n t r ea t ed n a t u r a l sou r ces a n d t h e h eav y r elia n ce on n a t u r a l p r od u ct s (Loga n , 1991, p. 65). Lea ch in g of h a za r d ou s w a st e in t o t h e w a t er st r ea m or d isp osa l n ea r sea sit es m ay b e h a za r d ou s t o m a r in e life, esp ecia lly fi sh , a n d ca u s e d a m -a ge t o ot h er -a sp ect s of t h e -a q u -a t ic ecosy st em . E st u a r ies or r iver d elt a s a r e p op u la r sit es for in d u st r y in d evelop in g cou n t r ies a s m a n y p op u la t ion cen t r es a r e sit u a t ed a t su ch p oin t s. E st u a r ies a r e im p or t a n t a r ea s for con ser va t ion a s w ell a s r ou t es for m igr a t or y fi sh es a n d fi sh p r od u ct ion (P et t s a n d E d u ljee, 1994, p. 163). Con t a m in a t ion of t h ese cr it ica l a r ea s of a q u a t ic b iologica l d iver sit y ca n lea d t o a dver se effect s su ch a s r ed u ct ion in t h e sea food h a r vest w h ich in t u r n ca n lea d t o d eb ili-t a ili-t in g effecili-t s on ili-t h e econ om y of m a n y d evel-op in g cou n t r ies.
T h e d evelop in g wor ld h a s s h ow n a gr ea t w illin gn ess t o im p or t h a za r d ou s w a s t es, yet wou ld a p p ea r t o b e t ot a lly u n p r e p a r ed for p a r t icip a t ion in t h e n efa r iou s a ct iv it ies m a s-q u er a d in g a s in t er n a t ion a l t r a d e. UN E P h a s id en t ifi ed som e of t h e p r oblem s fa cin g d evel-op in g cou n t r ies in t h e d is p osa l of h a za r d ou s w a st es. T h ese a r e p oor p ollu t ion con t r ol, la ck of fi n a n cia l r esou r ces, low level of p u blic aw a r en ess, la ck of st a ff w it h t ech n ica l a n d m a n a ger ia l sk ills, la ck of in fr a s t r u ct u r e for m a n a gem en t a n d con t r ol, a n d t h e gen er a l a b sen ce of d a t a on t h e gen er a t ion , t r a n sp or t a n d d isp os a l of h a za r d ou s w a s t es (Bisw a s, 1989, p. 265; Don a ld , 1992, p. 423; UN E P, 1993, p p. 329-39). A st u dy of t h e h a za r d ou s w a st e t r a d e in t h e Ca r ibb ea n Ba sin h a s n ot ed t h e a b sen ce of t h e t ech n ologica l k n ow led ge eit h er t o d isp ose of im p or t ed h a za r d ou s w a st e sa fely or t o p r ocess or r ed u ce it t o a n in n ocu ou s en d p r od u ct . F u r t h er, t h e st u dy r evea led t h e n on -exist en ce of t h e n ecessa r y eq u ip m en t or exp er t ise t o d et ect esca p e fr om t h e m ed iu m of con t a in m en t u sed for h a z-a r d ou s w z-a s t e. It w z-a s n ot ed t h z-a t t h e level of m ed ica l eq u ip m en t a n d exp er t is e t o d ia gn ose a n d t r ea t a ilm en t s r ela t ed t o h a za r d ou s w a st e d isp osa l w er e in v a r ia b ly a b sen t (Su it e, 1991, p. 223).
Non-hazardous waste
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w it h p r op er ly. T h e WH O h a s s t a t ed t h a t u n collect ed r efu s e p os es a s er iou s t h r ea t in d evelop in g cou n t r ies a s it is a m a jor fa ct or in t h e s p r ea d of ga s t r oin t es t in a l a n d p a r a s it ic d is ea s es, m a in ly a s a r es u lt of t h e p r olifer a -t ion of in s ec-t a n d r od en -t vec-t or s (UN E P, 1993, p. 331). T h e Br it is h Med ica l Ass ocia t ion h a s ob s er ved t h a t p oor m a in t en a n ce of sew er s, food w a s t e a n d t ip p in g ca n lea d t o in cr ea sed ca s es of le p t osp ir os is (Br it is h M ed ica l Ass oci-a t ion , 1991, p. 27). Ad d it ion oci-a lly, d u m p in g of m u n icip a l w a st es a t sit es n ea r s q u a t t er s or u r b a n set t lem en t s ca n lea d t o in cr ea sed r is k of p ois on in g a n d ot h er h ea lt h h a za r d s t o n ea r by occu p a n t s, in clu d in g t h ose w h o s cav -en ge a t d u m p s it es (UN E P, 1993, p. 331).
Sew a ge slu d ge is a ls o a p ot en t ia l a r ea of con cer n . Sew a ge slu d ge h a s gen er a lly b een d efi n ed a s a s lu r r y of or ga n ic r ich p a r t icles. T h is s lu d ge h a s a va r ia ble ch em ica l con t en t d e p en d in g on it s sou r ce a n d t h e efficien cy of t h e t r ea t m en t p r ocess. Sew a ge slu d ge ca n b e u sed a s fer t ilizer s or p r ocess ed in t o com p os t (UN E P, 1993, p. 339). T h e p r oblem is t h a t in m a n y d evelop in g cou n t r ies t h e t r ea t m en t of s ew a ge is in efficien t a n d t h e w a s t e s t r ea m is oft en m ixed w it h ot h er for m s of h a za r d ou s w a s t es. T h is cou ld lea d t o con t a m in a t ion of la n d s w h er e t h e slu d ge is a p p lied or gr ou n d w a t er in t o w h ich it is d is ch a r ged . T h e d a n -ger s of con t a m in a t ion of w a t er s y s t em s a n d la n d w it h s ew a ge a r e com p ou n d ed by t h e fa ct t h a t over 1.9 b illion p eop le in t h e d evelop in g wor ld d o n ot h ave a cces s t o s a n it a t ion fa cili-t ies (UN DP, 1994, Ta ble 3, p. 135). T h is r es u lcili-t s in d u m p in g of r aw sew a ge in t r a s h h ea p s, p u blic la n d a r ea s or w a t er cou r ses (Reich a r d , 1990, p. 13). Aga in , t h e d u m p in g of r aw s ew a ge ca n give r ise t o a h os t of d isea s es t h a t m ay a dver s ely a ffect t h e h ea lt h of m a n (Wor ld Ba n k , 1992, p. 54). Cr op s m ay a lso b ecom e con t a m in a t ed a n d con su m p t ion by h u m a n s m ay p r ove fa t a l. Ad d it ion a lly, h u m a n con -s u m p t ion of a n im a l-s t h a t h ave ea t en con t a m i-n a t ed fod d er ca i-n p r ov id e a p a t h w ay ii-n t o t h e b ody.
Noise pollution
N ois e p ollu t ion is n ot a n in ven t ion of m od er n m a n . M iln e (1979) h a s n ot ed t h a t J u liu s Ca es a r w a s so a n n oyed by t h e r e p et it ive t h u d of h or s e h ooves a n d t h e s ou n d of s p eed in g w h eels, t h a t h e a t t em p t ed t o b a n d ay t im e ch a r iot r a cin g (p. 16). H ow ever, n ois e p ollu -t ion is cer -t a in ly b ecom in g on e of -t h e les s d es ir a ble fea t u r es of t od ay ’s wor ld . T h e m a jor s ou r ces of n oise a r e gen er a lly h eav y m a ch in -er y a t wor k com p lexes, t r a n sp or t veh icles, h om e a p p lia n ces a n d leis u r e a ct iv it ies s u ch a s m u s ic (Kr y t er, 1985, p. 167). T r a n sp or t m ech a n is m s a r e by fa r t h e gr ea t es t p r od u cer s of a dver s e n oise levels. F r om m ot or veh icle t r a ffic in u r b a n cen t r es, t h e in d iv id u a l is
gen er a lly su b ject ed t o h igh n oise levels (Miln e, 1979, p p. 23-33). Sim ila r ly, t h e effect of n oise fr om a ir cr a ft a r ou n d t h e v icin it y of a ir p or t s is a n a r ea of gr ave con cer n . In d u st r ia l n oise or n oise st h a st em a n a st es fr om m a n u -fa ct u r in g com p lexes is of con cer n n ot on ly for t h ose liv in g in t h e a r ea w h er e t h e n oise is b ein g p r od u ced , bu t a ls o t o t h e em p loyees w h o a r e exp osed t o even gr ea t er levels over con sis t en t p er iod s of t im e (Miln e, 1979, p p. 34-40).
T h e effect s of n ois e p ollu t ion on m a n a r e m a n ifest ed a s b ot h a u d it or y a n d n on -a u d i-t or y sy m p i-t om s. On i-t h e a u d ii-t or y level, n oise p ollu t ion ca n lea d t o loss or d im in u t ion of h ea r in g a b ilit y. T h is is even m or e p r ofou n d a t p la ces of wor k w it h h igh n oise levels. N oise ca n d a m a ge or d est r oy t h e m icr oscop ic h a ir cells t h a t t r a n s m it sou n d fr om t h e ea r t o t h e b r a in , lea d in g t o b ot h t em p or a r y or p er m a -n e-n t d a m a ge (F a r u q u i, 1985, p. 189). Tem p or a or y d a m a ge occu or s if t h eor e is a n on p eor m a -n e-n t sh ift i-n t h e h ea r i-n g t h r esh old d u e t o n oise exp osu r e. Wh er e t h er e is r e p ea t ed exp o-su r e t o t h e h igh n oise levels over a lon g p er iod of t im e a s in a fa ct or y, t h er e is a gr a d u a l d et er ior a t ion in t h e or ga n of Cor t i r esu lt -in g -in a p er m a n en t sh ift of t h e h ea r -in g t h r esh old (Cu n n iff, 1977, p p. 101-2). It h a s b een clea r ly sh ow n t h a t p eop le su ch a s t h e Ma b a a n t r ib e of Su d a n w h o live in q u iet com m u n it ies p ossess fa r gr ea t er h ea r in g a b ilit ies t h a n p eop le in h a b it in g t h e in d u st r ia lized wor ld (F a r u q u i, 1985, p. 189).
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slee p a ffect s on e’s p er s on a l w ellb ein g a n d m ay im p a ct n e ga t ively on a ct iv it ies s u ch a s job p er for m a n ce (Cu n n iff, 1977, p. 111; Sh a p ir o, 1993, p. 75). Sp eech in t er fer en ce a ls o occu r s b eca u se of h igh n ois e levels a s it ca n b ecom e a s ou r ce of fr u s t r a t ion or lea d t o d is t or t ion s in t h e d evelop m en t of t h e s p eech level of a n in d iv id u a l. It is a lso on e of t h e h u m a n con s eq u en ces of en v ir on m en t a l n ois e p ollu t ion t h a t is con sid er ed w h en n oise r e gu -la t ion s a r e b ein g fr a m ed (Cu n n iff, 1977, p. 109). F in a lly, h igh n oise levels cr ea t e s t r es s a n d ca n lea d t o t h e d evelop m en t of feelin gs of a n n oya n ce, fr u st r a t ion , in t oler a n ce a n d m ood in ess (Sh a p ir o, 1993, p. 75). T h is level of st r ess m ay im p a ct a dver s ely on t h e p s ych o-logica l w ellb ein g of a n in d iv id u a l (Cu n n iff, 1977, p p. 111-3).
Light pollution
On e of t h e n ew a n d em er gin g a r ea s of en v i-r on m en t a l h a i-r m i-r ela t es t o ligh t p ollu t ion , a n d m ed ica l r esea r ch h a s u n cover ed a p ot en -t ia l m ed ica l effec-t on h u m a n s d u e -t o ligh -t p ollu t ion . It h a s b een a r gu ed t h a t a r t ifi cia l ligh t s h ou ld b e con sid er ed a s a n im p or t a n t com p on en t of ca r cin ogen es is (Ker en y i et a l., 1990, p. 76). T h e effect of ligh t is felt m a in ly t h r ou gh t h e p in ea l gla n d . It is gen er a lly a cce p t ed t h a t m ela t on in , t h e m os t sign ifi ca n t p in ea l h or m on e, p r od u ces a n on -s p ecifi c on cos t a t ic effect . T h e sy n t h es iza t ion of m ela -t on in -t a k es p la ce in d a r k n ess w i-t h p r od u c-t ion d im in is h in g in ligh t . Wit h t h e r ise of a r t ifi -cia l ligh t in g, t h er e h a s b een a d r a st ic in cr ea s e in d a ily exp osu r e t o ligh t . As a r es u lt , t h e p r od u ct ion t im e for m ela t on in fr om t h e p in ea l h a s b een s ever ely r ed u ced . T h is r ed u ct ion h a s con s eq u en t ly d ecr ea sed t h e on cos t a t ic effect s of m ela t on in , lea d in g t o s ign ifi ca n t in cr ea ses in t h e in cid en ce of t u m ou r s, p a r t icu la r ly a m on g t h e you n ger a ge gr ou p (Ker en y i et a l., 1990, p p. 76-7). It h a s a lso b een a r gu ed t h a t ligh t p ollu t ion ca n a ffect on e’s s lee p in g a b ilit y lea d in g t o in cr ea sed s t r es s (N ea le, 1995, p. 4).
Environmental degradation and
human health: the unknown factor
Acid rain
In s om e a r ea s of en v ir on m en t a l d e gr a d a t ion , t h e h u m a n h ea lt h r is k fa ct or is n ot fu lly u n d er s t ood , bu t is n ever t h eles s of gr ave con -cer n . On e s u ch a r ea is a cid r a in w h ich is ca p a ble of a ffect in g en t ir e r e gion s. T h e effect of a cid r a in on h u m a n h ea lt h h a s b een com -in g u n d er -in cr ea sed scien t ifi c scr u t -in y. So fa r a cid r a in h a s n ot b een s h ow n t o h ave a n y d ir ect effect s on h u m a n h ea lt h . T h er e m ay, h ow ever, b e som e in d ir ect effect s on h u m a n h ea lt h fr om a cid r a in . H eav y m et a ls s u ch a s
cop p er, zin c, ca d m iu m a n d m er cu r y a r e lib er -a t ed w h en soils -a n d d e p osit s -a r e -a cid ifi ed . T h ese con t a m in a n t s, w h ich a r e t oxic a n d st or ed in t h e h u m a n b ody r a t h er t h a n r elea sed , ca n in fi lt r a t e gr ou n d w a t er a n d en t er in t o t h e h u m a n sy st em . Ad d it ion a lly, t h ey ca n en t er t h e food ch a in by b ein g a b sor b ed by p la n t s w h ich in t u r n a r e con -su m ed by gr a zin g a n im a ls. H u m a n s con -su m e b ot h p la n t a n d m ea t s ou r ces, a n d t h u s t h e a ccu m u la t ion of m et a ls w it h in t h e b ody in cr ea ses (P a r k , 1987, p. 129). T h e fu ll effect s of t h e level of m et a ls is yet u n k n ow n bu t d is-ea ses lik e os t eom a la cia h ave b een lin k ed t o a lu m in iu m levels in d r in k in g w a t er.
Wellbu r n h a s a lso p oin t ed ou t t h a t d e p osit s of a lu m in iu m in t h e b r a in a r e n or m a lly seen in ca ses of Alzh eim er ’s d is ea se (Wellbu r n , 1988, p. 128).
H igh ly w a t er -solu ble a cid ic va p ou r s su ch a s su lp h u r d ioxid e ca n p en et r a t e t h e la r gest con d u ct ive a ir w ay s of t h e lu n gs d u r in g p er i-od s of p h y sica l exer cis e. T h e r es u lt is t h a t p eop le w it h h y p er -r ea ct ive a ir w ay s, su ch a s a st h m a t ics, ca n exp er ien ce w h ee zin g a n d sh or tn ess of br ea th (Lippm a n n , 1992, pp. 307-8). T h e exp osu r e of h u m a n s t o ch r on ic a n d cu m u la t ive d os es of a cid ic a er osols ca n lea d t o ch r on ic b r on ch it is (Lip p m a n n , 1992, p. 332). In J a p a n , sk in a n d eye ir r it a t ion h a s coin -cid ed w it h occa sion s w h en r a in fa ll h a s b een q u it e a cid ic (An d er s on , 1986, p. 711). F u r t h er, a cid ifi ca t ion of gr ou n d w a t er is b ecom in g a gr ow in g con cer n in t h e d evelop ed wor ld . T h e a cid ifi ca t ion of gr ou n d w a t er s is b ein g ob ser ved bu t t h e fu ll im p a ct is yet u n k n ow n . Acid ifi ca t ion of gr ou n d w a t er cou ld h ave h ea lt h im p lica t ion s d u e t o t h e solu b ilit y of t r a ce m et a ls fr om t h e soil a n d b ed r ock a n d m et a l p ip es in w a t er d ist r ibu t ion s y st em s (Br ick er a n d Rice, 1993, p p. 164-5). Wh ile t h er e a r e gr ave d ifficu lt ies in d et er m in in g con clu sively t h e r ole of a cid d e p osit ion in t h e d eclin -in g h ea lt h of h u m a n s, t h e p r oblem sh ou ld n ot b e u n d er est im a t ed a n d r eq u ir es con t in u ed r esea r ch .
Outer space
