Risk Profiling of Aflatoxin in Peanut (Arachis hypogaea L.) to the Filipino Consuming Population
Abigail S. Rustia1*, Christine Bernadette D.G. Mariano1, Karina Angela D. Bautista1,Deon Mahoney2, Erniel B. Barrios3, Casiana Blanca J. Villarino1, Mark R. Limon4, and Mario V. Capanzana5
1Department of Food Science and Nutrition, College of Home Economics, University of the Philippines Diliman, Quezon City, Metro Manila 1101 Philippines
2Produce Marketing Association Australia–New Zealand Ltd., Docklands, Victoria 3008 Australia
3School of Statistics, University of the Philippines Diliman, Quezon City, Metro Manila 1101 Philippines
4College of Teacher Education, Mariano Marcos State University, Laoag City, Ilocos Norte 2900 Philippines
5Food and Nutrition Research Institute, Department of Science and Technology, Taguig, Metro Manila 1630 Philippines
Aflatoxin (AFL) is a naturally occurring mycotoxin produced by Aspergillus spp. and is commonly associated with peanuts (Arachis hypogaea L.), a major field legume in the Philippines. The major types of AFL are B1, B2, G1, and G2 – comprising the total aflatoxin (AFT). AFL exposure has been shown to cause both chronic and acute toxicity, with the liver as the main target organ. It is considered genotoxic and carcinogenic. The objective of this study is to establish the profile of the potential risks associated with the consumption of peanuts contaminated with aflatoxin to the Filipino consuming population. The study included [1] determination of data gaps in the risk profiling of AFL in the consumption of peanuts by the Filipino peanut-consuming population;
[2] hazard identification and characterization; [3] estimation of dietary exposure (DE) and risk- based on uncertainties, variabilities, and assumptions; and [4] consolidation of available control measures and possible mitigation protocols for AFL in peanut. AFL was detected in 92% of all the peanut samples (n = 50) analyzed, with overall mean levels of 802.83 µg/kg AFT, 683.53 µg/kg AFB1, and 119.30 µg/kg AFB2 exceeding the maximum level (ML) of 15 µg/kg set by the Codex Alimentarius Commission for AFT. Considering the assumptions made and data gathered in this study, the estimated daily intakes (EDIs) of the Filipino adult (20–59 yr old) consuming population to AFT and to AFB1 in peanut – at 97.5th percentile consumption – were 1.22–6,527.18 ng/kg body weight (bw)/dand 1.22–5,574.90 ng/kg bw/d, respectively, which exceeded the recommended provisional maximum tolerable daily intake (PMTDI) of 1 ng/kg bw/d. The margins of exposure (MOE) were also generally estimated to be below 10,000, which indicates that it is a potential health concern and that it supports the need for further risk management actions.
Key words: aflatoxin, peanut, Philippines, risk, risk profile
*Corresponding author: [email protected]
ISSN 0031 - 7683
Date Received: 27 Jul 2021
INTRODUCTION
Aflatoxin (AFL) is a naturally occurring mycotoxin produced by species of the mold Aspergillus spp.
– particularly, A. flavus and A. parasiticus – which contaminate food crops and pose serious health threats to humans and animals (FAO 1993; Arim 2003; Moss 2003;
IARC 2012; WHO 2018a). Numerous types of AFL have been identified throughout the years, but four major AFLs (AFB1, AFB2, AFG1, and AFG2) are found in all major food crops and are considered particularly dangerous to humans and animals, as metabolites from this mycotoxin may cause mutations (mutagenic) and toxicity (genotoxic and carcinogenic) in the human body (IARC 2012;
WHO 2018a, b). AFL has been first evaluated by IARC (International Agency for Research on Cancer) Working Groups and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1971 and 1987, respectively, and has since been studied to have sufficient evidence for its carcinogenicity in humans – particularly of the liver (hepatocellular carcinoma) and, thus tagged as a Group 1 agent (WHO 1987, 2018b; IARC 2002, 2012). At the 49th JECFA meeting, potency estimates for human liver cancer resulting from AFB1 exposure with Hepatitis B virus surface antigen (HBsAg) status considered were also provided (WHO 2018b). Among the major types of AFL, AFB1 is considered the most potent and accounts for 75% of AFL contamination in foods and feeds (Coppock and Christian 2007; Wacoo et al. 2014). One such crop susceptible to AFL contamination is peanut (IARC 2012;
Bediako et al. 2019).
Peanut (Arachis hypogaea L.) or groundnut, locally known as mani, is one of the major field legumes grown by local farmers in the Philippines (Palomar 1998; DA-BPI 2016). It is an edible legume crop, belonging to the family Fabaceae, highly valued and consumed for its nutritional content and functionality (Sanders 2003; Arya et al.
2015; DA-BPI 2016). From 2008–2018, the Philippines produced an average of 29,447.62 metric tons (MT) of peanuts, with the highest production of 30,977.83 MT achieved in 2009 and the lowest at 27,920.92 MT in 2016 (DA 2014; PSA 2018). In 2018, a total of 29,428.47 MT of peanuts was produced in the country, with the top peanut- producing region – Region I (Ilocos Region) – accounting for 40.81% of total peanut production (PSA 2018).
Peanuts are associated with A. flavus and A. parasiticus and are among the food commodities with the highest risk of AFL contamination (IARC 2002, 2012; Santini and Ritieni 2013). The formation of AFL may occur during various stages of peanut production, from storage to processing (FAO 1993; FAO-IAEA 2001; Coppock and Christian 2007; Santini and Ritieni 2013). Pre-harvest contamination of crops with AFL happens when seeds are stressed and made susceptible to mold invasion by
stressors such as drought, insect infestation, and irrigation timing (Coppock and Christian 2007; IARC 2012).
Agricultural practices such as crop rotation and soil cultivation are also factors affecting AFL contamination (Dors et al. 2011). Once harvested, AFL production and contamination in crops such as peanuts may still occur when favorable storage and environmental conditions are met, especially in a tropical or subtropical climate (Coppock and Christian 2007; Santini and Ritieni 2013).
Hence, AFL contamination in peanuts was considered a serious problem in several Asian countries, including the Philippines (Mehan and Gowda 1997). It does not only reduce the quality and quantity of marketable peanuts, which hinders trade, but it also poses adverse health effects to the consumers through the metabolites it produces, which renders the commodity unsafe for consumption (Balendres et al. 2019; Bediako et al. 2019).
Numerous research efforts have been made throughout Asia to determine the impact of AFL contamination as well as its management (Mehan and Gowda 1997). In the Philippines, AFL research began as early as 1967 when the Philippine Department of Science and Technology–Food and Nutrition Research Institute (DOST-FNRI) initiated surveillance and monitoring studies to determine AFL content in various foods, where it was found that from 1967–1982, raw peanuts from regular outlets and from different regions in the Philippines contained high levels of AFL amounting to < 3–2,888 µg/kg and < 3–600 µg/kg, respectively (Garcia 1989; Garcia and Beuchat 1995; Arim 1995). Since then, different studies have been conducted in pursuit of new information regarding mycotoxin (Bulatao- Jayme et al. 1982; Garcia 1989; Galvez et al. 2003; Rustia et al. 2011). However, knowledge of the practices and measures of controlling AFLs in the Philippines is still limited (Balendres et al. 2019).
This study sought to gather and establish updated baseline data in the form of a risk profile to determine the presence of any health risk accompanied by the consumption of AFL-contaminated peanuts in the country. Specifically, this study aimed [1] to determine the gaps in data and information needed for the risk profiling of AFL in the consumption of peanuts by the Filipino peanut-consuming population, [2] to identify and characterize AFL as a hazard in peanut based on literature review, [3] to estimate the level of risk of AFL in peanut to the Filipino peanut consumers through dietary exposure (DE) assessment in consideration of the assumptions used in the study, and [4]
to determine the available control measures and possible mitigation strategies for AFL in peanut.
The process of risk profiling is also described as
“qualitative risk assessment” (WHO 2020). The resulting risk profile sought to serve as reference material for risk managers in evaluating risks to the Filipino consuming
population and to aid in the decision-making and proposition of possible mitigation measures. This study was conducted from 2019–2020 under the DOST–
Philippine Council for Industry, Energy and Emerging Technology Research and Development (PCIEERD) Project No. 05340, known as the Philippine Food Safety Risk Profiling Project (PRPP).
MATERIALS AND METHODS
The food hazard:commodity combination was identified, and the risk management questions were formulated after consultations with the risk analysis expert and food safety advisor of the PRPP and with concerned government agencies – including the Department of Agriculture–
Philippine Coconut Authority (DA-PHILCOA) and the DA–Bureau of Plant Industry (DA-BPI). This risk profile focused on peanut (Arachis hypogaea L.) in the Philippines as the food commodity and AFL as the food hazard.
The outline of the risk profile was conceptualized with reference to the existing risk profiles from international organizations – such as CAC (CXG 63-2007 and CXG 30-1999) (CAC 2008, 2014a), FAO/WHO (2003), and United States (US) Environmental Protection Agency and Department of Agriculture/ Food Safety Inspection Service (US EPA and USDA FSIS 2012) – and based on consultations with the PRPP risk analysis and food safety expert.
Phase 1: Determination of Data Gaps in the Risk Profiling of AFL in the Consumption of Peanut (Arachis hypogaea L.) by the Filipino Peanut- consuming Population
This study conducted a narrative review to cover the five main sections of the conceptualized risk profile: [1]
hazard identification, [2] hazard characterization, [3]
exposure assessment, [4] risk characterization, and [5]
availability of hazard control measures. The aim of risk profiling was to identify the available information and the data gaps per section of the risk profile, particularly in the Philippine context.
Search strategy. The works of literature in this study were gathered from [1] academic research databases such as ScienceDirect (Elsevier), Wiley Online Library, Taylor & Francis Online, PubMed, J-Stage, Hindawi, and Wageningen Academic Publishers; [2] international reports and publications from the FAO, WHO, Codex Alimentarius Commission, and European Food Safety Authority; and [3] Philippine government websites and databases such as DA–Bureau of Agriculture and Fisheries
Standards (DA-BAFS), DA-BPI, Department of Health (DOH), DOST-FNRI, and Philippine Statistics Authority (PSA). Meanwhile, access to other pertinent documents relevant to the study of AFL in peanut was requested from collaborating agencies and offices such as the DOST- FNRI and the Philippine Food and Drug Administration.
The terms, “aflatoxin,” “peanut,” “peanut in the Philippines,” “aflatoxin in the Philippines,” “aflatoxin in peanut,” and “risk profile of aflatoxin” were used either individually or in combinations for the search for available information – including the scientific studies, standards, monitoring, evaluation, health risk assessment, reports of illnesses, and statistics relevant to peanut contaminated with AFL. Other pertinent terms were used depending on the section of the risk profile, e.g. “production data,”
“maximum level,” “consumption data,” and “exposure.”
Inclusion criteria. The general criteria for inclusion in this study are as follows: [1] the language of the publication is English or Filipino and [2] the database is accessible showing at least the abstract or the executive summary. For the exposure assessment: [1] available AFT occurrence studies in raw peanuts from the Philippines and Asia; [2] AFL DE studies from the Philippines, ASEAN countries, and other tropical or subtropical countries; and [3] available peanut consumption data of the Philippine population. For the control options: [1] food safety regulatory limits for AFL, particularly AFT and AFB1;
and [2] locally and international standards and regulations for the prevention, control, and/or reduction of AFL. A summary of which information is readily available and which is still lacking to complete the sections of a risk profile is tabulated (Table 1) to give an overview if a comprehensive risk management decision based on the current risk profile alone can be done.
Phase 2: Hazard (AFL) Identification and Characterization
The hazard identification in this study includes the sources of the hazards, particularly the conditions that influence its production (Table 2), and hazard in the specific food.
The hazard characterization, on the other hand, involves distribution and pharmacokinetics, adverse effects, dose-response, the establishment of food safety limits, the Filipino adult consuming population, and Philippine reports of poisoning or illness.
Phase 3: Estimation of DE and Risk-based on Uncertainties, Variabilities, and Assumptions
Formulation of assumptions based on identified uncertainties and variabilities. The overall degree of confidence in the DE and risk estimates was discussed in the context of assumptions. The limitations, uncertainties
(data gaps), and variabilities identified before and along the process of risk profiling were considered in the formulation of the assumptions.
In this study, limitations were defined as the restrictions in the conduct of risk profiling and survey for the generation of data on AFL levels. The uncertainties were defined as the data gaps needed to be addressed or minimized to further the risk assessment and to come up with a more comprehensive risk estimate for the Filipino consuming population. Meanwhile, the variabilities were defined based on FAO (1995) as the information used in risk profiling that is constantly varying and cannot be represented by a single value but can be addressed with precision. From these, assumptions were formulated and used to calculate the DE and risk estimates. Assumptions were defined as the limitations and the scope of risk profiling in consideration of the inevitable gaps in the risk profiling process.
Ethical considerations. The exposure pathway assessment conducted for the PRPP, particularly in this study, involved interactions with the stakeholders. As such, the project has applied for ethics clearance through the National Ethics Committee (NEC) of the DOST–Philippine Council for Health Research and Development and the Philippine National Health Research System. The application has been approved with the NEC Code: 2019 014 Rustia Hazards (20190822-115 NEC).
Survey and sampling. The exposure of the Filipino population to AFL in peanuts was first assessed by generating data on AFL (AFB1, AFB2, AFG1, AFG2, and AFT) levels in peanuts in the Philippines through survey and sampling based on the Guidelines for the Survey of Aflatoxin (Arachis hypogaea L.) by the PRPP and as consulted with the Statistical Science Expert.
The sampling design was based on directed or targeted sampling (CXG 71-2009) (CAC 2014b), particularly targeting the worst-case settings (CXG 50-2004) (CAC 2004a). The sampling plan was purposively intended to cover places with the highest production of peanuts, which were assumed to have higher exposure levels (e.g.
provinces with the presence of anthropogenic, and high production of peanuts) to account for the worst-case scenario in terms of exposure to and consumption of peanut contaminated with AFL. Sampling in this study was recommended by the Statistical Science Expert to be conducted with at least four replicates.
The sampling locations (Table 3) were identified using data on the top peanut-producing provinces based on the PSA 2018 Annual Peanut Production data, accessed from the PSA OpenStat Database. The survey and sampling were conducted in the month of November 2019. A total of 50 peanut samples from the five identified provinces were submitted to the identified laboratory in December 2019.
Sample analysis. Collected peanut samples were submitted to SGS Thailand for multi-mycotoxin analysis (AFB1, AFB2, AFG1, AFG2, and AFT) using liquid chromatography with tandem mass spectrometry (LC- MS/MS) [in-house method SOP no. LBLC-18004 based on QuEChERS method; limit of detection (LOD) = 0.25;
limit of quantification (LOQ) = 0.50]. The selection of the laboratory was based on the following criteria:
[1] the laboratory to be selected must be ISO/IEC 17025-accredited, and [2] the analytical service offered by the laboratory must align with the standard method of analysis for the AFL in peanut (AOAC Official Method 990.33: Aflatoxins in Corn, Raw Peanuts, and Peanut Butter Using Immunoaffinity Column Method).
Data on AFL levels in peanut samples (Table 3) were consolidated, analyzed, and expressed as mean (±
standard deviation or SD) AFL (AFB1, AFB2, AFG1, AFG2, and AFT). One-way analysis of variance was used to determine whether the calculated AFL levels differ significantly between the sampling points (grouped per province). AFL levels (µg/kg) in peanuts from studies in the Philippines (Table 4) and in Asia (Table 5) were also reported for comparison.
Calculation of DE and risk estimates. Estimates of the DE, or the daily intake (EDI), of Filipino adult males and females aged 20–59 yr old were then calculated using Equation 1 (WHO 2020):
Estimated daily intake (EDI)
�(Food consumption x Chemical concentration in the food)
Mean body weight (kg)
= (1)
The EDI values (Table 6) were then compared with the provisional maximum tolerable daily intake (PMTDI) of 1 ng/kg bw/d recommended by Kuiper-Goodman [1995, 1998; as cited in Magrine et al. (2011)] and with the international dietary estimates from the literature review (Table 7). Peanut consumption data of the Filipino consuming population from other sources were also shown in Table 8.
There are several approaches that can be used for characterizing the risk of substances that are both genotoxic and carcinogenic such as AFL, one of which is the margin of exposure (MOE) approach recommended by the European Food Safety Authority (EFSA 2005).
Unlike other approaches, which result in very different conclusions for one substance when estimating the risk through extrapolation using high dose levels in animal studies to translate to human exposure levels usually in much lower doses, the MOE approach uses a reference point corresponding to a dose at which a low but measurable response can be observed, which is then compared with different dietary intake estimates in
humans (EFSA 2005, 2012). Hence, the MOE represents the ratio between “the dose at which a small but measurable adverse effect is first observed and the level of exposure to the substance considered” (EFSA 2012).
The EFSA Scientific Committee also recommended the use of the benchmark dose lower confidence limit of 10%
(BMDL10) as a reference point in calculating the MOE since it is the “lowest statistically significant increased incidence that can be measured in most studies, and would normally require little or no extrapolation outside the observed experimental data” (EFSA 2005). The lowest BMDL10 value at 170 ng/kg bw/d was used in this study, as derived by EFSA (2007) from animal data (Fischer rats) and used for risk management of AFB1 in Indonesia, as indicated in the study of Nugraha et al. (2018).
The MOEs in this study (Figures 1 and 2) were calculated by dividing the reference point by the estimated daily intakes (EDI), as shown in Equation 2 below:
Benchmark dose lower confidence limit for 10% extra risk BMDL10)
Estimated daily intake (EDI)
Margin of
Exposure (MOE) = (2)
The MOE approach indicates the level of safety concern of a substance present in food without quantifying the risk, which in turn helps risk managers define possible actions and set priorities to keep exposure to such substances as low as possible (EFSA 2012). Using the BMDL10 as the reference value, an MOE value lower than 10,000 would mean that the substance is of concern from a public health point of view and can be considered a priority for risk management actions (EFSA 2005).
Phase 4: Consolidation of Available Control Measures and Possible Mitigation Protocols of AFL in Peanut
The information on the available risk management options for AFL in peanut from gathered and reviewed literature discussed the existing control measures in the Philippines:
regulatory and advisory, control measures employed overseas, and control options.
RESULTS AND DISCUSSION
Phase 1: Determination of Data Gaps in the Risk Profiling of AFL in the Consumption of Peanut (Arachis hypogaea L.) by the Filipino Peanut- consuming Population
The list of available information gathered from the narrative review and the data gaps identified for each section of the risk profile for AFL in peanut (Arachis hypogaea L.) in the Philippines was consolidated in Table 1. It also details which information is readily available and
which is still lacking, especially in the Philippine context.
In identifying the gaps, the risk managers (i.e. DA-BPI, DA-BAFS, DA-PHILCOA, etc.) are also presented with options for further action.
Phase 2: Hazard (AFL) Identification and Characterization
Identification: sources of the hazard. AFL-producing molds grow in a wide range of agricultural crops such as corn, peanuts, coconuts, and cassava (Arim 2003). A. flavus and A. parasiticus are the two most prominent Aspergillus species producing AFL in agricultural commodities (Nicholson 2004; Horn 2005). A. flavus produces AFLs B1 and B2 in peanuts, corn, cottonseed, and tree nuts before harvest and during storage (Horn 2005; WHO and FAO 2018a). The most prevalent species in peanuts, however, is A. parasiticus – which produces both the B and G group AFLs (Horn 2005). Aside from peanuts, A. parasiticus also contaminate corn, figs, and pistachios (WHO and FAO 2018a). Other Aspergillus species that produce AFL include A. nomius, A. bombycis, A. ochraceoroseus, A.
pseudotamari, and A. fumigatus (Horn 2005; Nicholson 2004; Coppock and Christian 2007; Santini and Ritieni 2013). Table 2 shows the conditions – water activity and temperature – influencing the growth of A. parasiticus and A. flavus, and AFL production.
Identification: hazard in the specific food. Biosynthesis and occurrence of AFL contamination in agricultural products are influenced by environmental factors, geographic location, as well as agricultural and agronomic practices (Santini and Ritieni 2013). AFL formation may occur during crop production, storage, and processing – and is favored by poor storage, environmental conditions, and a tropical or subtropical climate (FAO 1993; FAO- IAEA 2001). In the Philippines – particularly in the Ilocos and Cagayan Valley regions, known to be the major peanut-producing areas – the peanut value chain consists of the following steps: harvesting, windrow-drying, stripping, drying, storing, shelling, cleaning, sorting/
grading, and marketing (DA 2014). Along this peanut value chain, mold contamination may occur during pre- harvest, harvest, windrow drying, sun drying, sorting, storing, trading, and processing (FAO-IAEA 2001).
Characterization: distribution and pharmacokinetics.
AFLs are produced through a polyketide pathway. AFB1 is introduced into the body either by ingestion of an AFL- contaminated food or by inhalation of dust particles from AFL-contaminated foods (FAO 1993; Bbosa et al. 2013).
It is absorbed across cell membranes and is distributed to the different tissues of the body through blood circulation (Bbosa et al. 2013). From the digestive tract, AFB1 is absorbed into the hepatic portal blood and is carried into the liver (Coppock and Christian 2007). It is then broken
Table 1. List of available information gathered from RRL and data gaps identified for every step (and subtopics of each step) of the risk profile for aflatoxin in peanut (Arachis hypogaea L.) in the Philippines.
Needed information to complete
the risk profile Available information Gaps identified
Hazard identification
Definition and sources of aflatoxin;
conditions influencing mold growth and aflatoxin production of Asper- gillus species
- Reports on aflatoxin from the FAO and WHO - Information from academic journals, Philippine
government websites such as the DA, textbooks, and other publications
- None for this part
Hazard characterization Distribution and pharmacokinetics of aflatoxin; adverse health effects;
dose-response studies on aflatoxin
- Reports on Aflatoxin from the FAO, IARC, WHO, and JECFA
- Academic research journals and international publications
- Internationally available dose-response studies
- None for this part
Health-based guidance values - ML set by CAC for AFT in peanuts
- Recommended provisional maximum tolerable daily intake (PMTDI) for aflatoxin by Kuiper-Goodman (1995, 1998) for adults, not carriers of the hepatitis B virus [as cited in Magrine et al. (2011)]
- Lack of the capacity of local laboratories to test for AFT; laboratory analysis readily available within the country is for Aflatoxin B1 (at the time of sampling in this study) Exposure assessment
Local peanut production data - The Philippine Statistics Authority (PSA) 2018
Annual Peanut Production Data and Philippine DA - None for this part Local aflatoxin concentrations in
peanut - Local studies by Bulatao-Jayme et al. (1982), Garcia (1989), Galvez et al. (2003), and Rustia et al. (2011) - Overseas study by Lien et al. (2019) on imported
peanut and peanut products from the Philippines
- Limited local data on the occurrence and concentration of aflatoxin in peanut
International aflatoxin concentration
in peanut - International studies on the occurrence and concentration of AFT in raw peanuts in Asia, particularly in Pakistan, China, Thailand, and Yemen - Other academic journals and reports from the FAO
and WHO
- None for this part
Local peanut consumption infor-
mation - Peanut consumption data of the Philippine population in 2010 from FOSCOLLAB (WHO and FAO 2018b) and in 2013 and 2015 (DOST-FNRI 2015, 2016) - Disaggregated consumption data from the 2013
National Nutrition Survey (notarized 2020, pers.
comm., DOST-FNRI)
- None for this part
Comparison of Philippine dietary
exposure with overseas estimates - Dietary exposure calculations from several international studies from Malaysia, Brazil, Vietnam, Malaysia, and Indonesia
- Other academic journals
- None for this part
Sampling protocols for aflatoxin in
peanuts - Codex Sampling Protocol for Total Aflatoxin in peanuts (intended for further processing) (CXS 193-1995 e. 2019)
- General Guidelines on Sampling (CXG 50-2004)
- Limited application of the existing CODEX sampling protocol (CAC 1995) for aflatoxin in peanuts (intended for further processing) to the Philippine peanut industry (the Codex sampling plan follows lot weights of peanut measured in tons; however, the peanut farmers in the Philippines only produce and harvest peanut in kg).
Risk characterization
Estimate of risk for the Philippines - MOE approach as recommended by EFSA - MOE findings from the Executive Summary of Risk
Assessment on the “Total Aflatoxins (AFT) and Aflatoxin B1 (AFB1) through the Consumption of Peanut and Corn” (ARAC 2020); MOE values from the studies of Leong et al. (2011), Nugraha et al.
(2018), and Do et al. (2020) - Other academic journals
- Limited reports on aflatoxin-related illnesses in the Philippines.
down into epoxides and other metabolites inside the liver’s microsome which react with the DNA or RNA, or bind to protein, further resulting in changes and damages in the nucleic acid sequence and affecting the normal function of the cells in the human body (Bbosa et al. 2013; Wacoo et al. 2014).
Characterization: adverse effects. AFL was evaluated as a potent hepatocarcinogen with AFB1 being a potential human carcinogen (WHO 1987, 2018b). It was then categorized by the IARC under Group 1 which indicates that it has sufficient evidence for being carcinogenic to humans (IARC 2002, 2012, 2019). Aflatoxicosis, the general term used for the disease brought upon by the ingestion of AFL, is usually classified as either acute or chronic (Williams et al. 2004; Santini and Ritieni 2013).
Acute aflatoxicosis is characterized by hemorrhagic necrosis of the liver, bile duct proliferation, edema, lethargy, and eventually results in death (Williams et al.
2004; Santini and Ritieni 2013). Chronic aflatoxicosis, on the other hand, results in cancer, immunologic suppression, nutritional interference, and other slow pathological conditions (Santini and Ritieni 2013).
Characterization: dose-response. Numerous studies on animals have been conducted to determine the carcinogenicity of AFLs (IARC 2012; WHO and FAO 2018a). Toxicological studies were performed on various laboratory animals such as transgenic mouse, rat, tree
shrew, and trout with varying doses of AFB1 (IARC 2012; WHO and FAO 2018a). Dose-response relationship studies for AFL specifically discussed in the food safety risk profile were acquired from Cupid et al. (2004), Chen et al. (2010), and Supriya et al. (2016).
A study conducted by Cupid et al. (2004), where data from tests on Fisher rats and human volunteers were deemed closely fit, found that formation of the AFB1-albumin adducts increases as the dose increase with the following order of formation within the tissues: liver > kidney > colon
> lung = spleen (Cupid et al. 2004). Meanwhile, results from Chen et al. (2010) showed a significant increase in liver mutant cells of neonatal mice when treated with a tumorigenic dose of 6 mg/kg AFB1 and no significant effect on the mutant frequency in adult mice with 6 and 60 mg/kg AFB1, which suggested higher sensitivity of young children to AFB1 mutagenicity and, therefore, higher risk to AFB1 compared to adults (Chen et al. 2010). Supriya et al. (2016), on the other hand, investigated the effects of prenatal exposure of varying doses (10, 20, 50, and 100 µg/
kg bw/d) of AFB1 on fertility output of dams (Wistar rats) on Days 12–19 of gestation and on postnatal developments of the female offsprings. The results showed that exposure of dams to AFB1 during gestation severely compromises postnatal development of neonatal rats, as manifested by significantly lower body weight and crown-rump length, as well as slower behavior and reproductive development.
Availability of hazard control measures
Existing control measures (locally
and overseas); control options - PNS Code of Practice for the Prevention and Reduction of Aflatoxin Contamination in Peanut (PNS/BAFS 175:2015)
- Codex Code of Practice for the Prevention and Reduction of Aflatoxin Contamination in Peanuts (CAC/RCP 2004b)
- Food safety regulatory limits for aflatoxin in various countries and organizations
- Lack of available and updated surveillance/
monitoring data and disaggregated data on aflatoxin levels in raw peanuts in the Philippines; FNRI surveillance on aflatoxin content of various foods were conducted from 1967–1982
Table 1. Cont.
Needed information to complete
the risk profile Available information Gaps identified
Table 2. Conditions influencing mold growth and aflatoxin production of Aspergillus species.
A. parasiticus A. flavus
Water activity (Aw) Temperature
(°C) Water activity
(Aw) Temperature
(°C)
Mold growth ≥ 0.83a
0.99*b 30*a
35*b 0.82–0.998a
0.98*c 10–43a
37*c Aflatoxin production ≥ 0.87a
0.98–0.99*b 28*a
37*b 0.92–0.96c
0.96*c 15–37a
28*c
*Optimum condition aFAO-IAEA (2001) bSchmidt-Heydt et al. (2010)
cLiu et al. (2017), specifically for shelled peanuts
It also causes irregular estrus with suppressed fertility output (Supriya et al. 2016).
Characterization: establishment of food safety limits for the Filipino adult consuming population. Developed countries generally have less than 1 ng/kg bw/d mean AFL DE, whereas some sub-Saharan African countries exceed 100 ng/kg bw/d (WHO 2018a). Considering that AFLs are genotoxic carcinogens affecting the human liver, biological thresholds in the dose-response relationship such as NOAEL (no observed adverse effect level) and LOEL (lowest observed effect level) are not established (Vettorazzi and de Cerain 2016; WHO and FAO 2018a).
An ML of 15 µg/kg was set by the CAC to regulate AFT in peanuts intended for further processing, which was adopted by the Philippine National Standard (PNS) on the Code of Practice (COP) for the Prevention and Reduction of Aflatoxin Contamination in Peanuts (CXS 193-1995 e. 2019; PNS/BAFS 175:2015). Recommended PMTDI for AFL is at 1.0 ng/kg bw/d, which is recommended by Kuiper-Goodman (1995, 1998) for adults, not carriers of the hepatitis B virus [as cited in Magrine et al. (2011)].
The value is also used for estimating the cancer potency per 100,000 population for exposure to AFB1 (WHO and FAO 2017).
Characterization: Philippine reports of poisoning or illness. As of writing, there were no published reports directly attributing AFL to liver cancer in the Philippines.
However, studies were conducted on the association of the disease to AFL exposure.
A study conducted by the DOST-FNRI from the year 1967–
1982 to determine the possible relationship between the consumption of AFL-contaminated corn by Filipinos and the development of primary liver cancer found that corn- eating regions have higher primary liver cancer incidence compared to rice-eating regions and have further shown that AFL-contaminated corn was aggravated by alcohol consumption (Arim 1995). Another study conducted by Denning et al. (1995) investigated the potential role of AFLs in acute lower respiratory infections (ALRI) of Filipino children. In this study, AFL in the serum and urine was used to indirectly measure actual AFL consumption of selected Filipino children (aged under 13 yr old) with ALRI. AFL was detected in 33% of the children’s sera (n = 114) with mean and median concentrations of 462 and 140 pg/mL, respectively, with a range of 20–5,600 pg/mL. AFL metabolites were detected in 98.46% of the children’s urine (n = 65) with a range of 0.1–4.77 ng/mL and with a mean AFL metabolite/creatinine ration of 1.27 ng/mL. Results showed that the urinary AFL metabolite/
creatinine ratio was not significantly associated with any outcome variable. No significant association was found between the time since the intake of the last meal (≥ 12 hr) and the detection of AFL, as well as the diminished
consciousness level and detection of AFL concentration.
Meanwhile, results of sample analyses and survey responses were utilized in the subsections on exposure assessment and risk characterization. A total of 50 peanut samples were analyzed for multi-mycotoxin analysis (AFB1, AFB2, AFG1, AFG2, and AFT) using LC-MS/
MS (in-house method SOP No. LBLC-18004 based on QuEChERS method).
Phase 3: Estimation of DE and Risk-based on Uncertainties, Variabilities, and Assumptions
Formulation of assumptions based on identified uncertainties and variabilities. Prior to the conduct of risk profiling, limitations of the study were identified to determine the range of information needed to adequately reflect the Philippine scenario.
Variabilities in the assessment were the following:
1. AFL has different types, four of which are considered the most dangerous;
2. different factors affect AFL production by Aspergillus spp.;
3. information gathered regarding the hazard is mostly from internationally published papers, whereas local monitoring/surveillance and studies on AFL in peanuts are outdated and scarce, if not at all available;
4. peanut stakeholders from the top-producing areas have different agricultural practices and stages of production, which affects levels of AFL in peanuts;
5. the nature of the peanut samples varies individually but are taken collectively; and
6. there are different responses and practices across respondents (peanut stakeholders).
The following uncertainties or data gaps were identified along the process of risk profiling:
1. there are limited reports on AFL-related illnesses in the Philippines;
2. there is a lack of updated surveillance/monitoring data and disaggregated data on AFL levels in peanuts in the Philippines, and FNRI surveillances on AFL content of various foods were conducted from 1967–1982;
3. local laboratories also lack the capacity to test for AFT, readily available laboratory analysis within the country at the time of the study was for AFB1 only, but the ML set by CAC is for total AFL (AFT);
4. existing sampling protocol for AFT in peanuts (intended for further processing) is not applicable to
the Philippine peanut industry and the objectives of the project;
5. according to key informant interviews conducted, it was found that there is limited awareness of mycotoxin and AFL in peanuts in the Philippines; and
6. there is no mandatory training or seminar on AFL and its risk to the concerned.
As a result, the following assumptions were made for the estimation of the DE and risk of AFL in peanuts to Filipino consumers:
1. AFL levels vary at every stage of the peanut production and in between locations;
2. the sampling locations identified represents the whole country of the Philippines;
3. the bw of the adult Filipino population is equal to the assumed bw for the adult Asian population, which is 55 kg (WHO 2020);
4. the disaggregated consumption data for peanuts acquired through a memorandum of understanding with the DOST-FNRI (notarized 2020, pers. comm.) represents the consumption of all male and female Filipino adults (20–59 yr old) consuming population in the Philippines; and
5. the 97.5th percentile consumption data of the Filipino consuming population was used to provide the most conservative estimate in the computation of the DE (WHO 2020).
Levels of AFL in peanut in the Philippines compared with local and overseas data. The results of the AFL contamination (AFB1, AFB2, AFG1, AFG2, and AFT) are shown in Table 3. AFLs were detected in 92% (46 out of 50) of all the raw peanut samples analyzed. The data shows a high incidence of AFB1, AFB2, and AFT in peanut samples (n = 50), whereas AFG1 and AFG2 were not detected in any of the contaminated samples.
The overall mean AFT level of the peanut samples was 802.83 µg/kg with an overall mean AFB1 level of 683.53 µg/kg and an overall mean AFB2 level of 119.30 µg/kg.
The AFT level of the peanut samples ranged from 0.51 µg/
kg (AFB1 level of 0.51 µg/kg) in Pangasinan to 2,736.24 µg/kg (AFBI level of 2,337.04 µg/kg and AFB2 level of 399.20 µg/kg) in Ilocos Norte. Although there were no significant differences (α = 0.05) in the AFL levels across provinces (p-values of 0.47, 0.49, and 0.38 for AFT, AFB1, and AFB2 levels, respectively), high SD values were calculated, which indicated the wide distribution of AFL level among the samples.
Throughout the years, high and toxic levels of AFL in peanuts in the Philippines have been detected and recorded, as can be seen in Table 4 (Bulatao-Jayme et al. 1982; Garcia 1989; Galvez et al. 2003; Rustia et al.
2011). AFL levels from these local studies also showed wide ranges, which was consistent with the results of this study. AFL-contaminated lots are known to have a highly heterogeneous distribution among peanut kernels, which may explain the wide range of AFL levels detected in these studies (Cucullu et al. 1966; Aoun et al. 2020). More importantly, the AFL levels far exceeded the Philippine regulatory limit or ML of 15 µg/kg.
Table 3. Aflatoxin levels (µg/kg) of peanut in the Philippines in 2019 Provinceb City/
municipality No. of samples (dried, shelled
peanuts)
Aflatoxin levels (µg/kg)a
mean ± SD Maximum
level (µg/kg)d
AFB1 AFB2 AFG1 AFG2 AFT
Ilocos Sur Santa Lucia 12 30.50 ± 54.02 2.36 ± 3.01 ND ND 32.86 ± 56.85
15 Ilocos Norte Vintar 12 2337.04 ± 3463.24 399.20 ± 600.60 ND ND 2736.24 ± 4044.77
La Union Balaoan 12 465.50 ± 566.22 91.03 ± 127.26 ND ND 556.52 ± 688.54
Pangasinan Sta. Barbara, Malasiqui,
Urdaneta
10e 0.51 ± 0.20 ND ND ND 0.51 ± 0.20
Isabela Cauayan 4 43.71 ± 78.62 13.48 ± 24.39 ND ND 57.18 ± 103.01
Overall Mean 683.53 ± 1918.29 119.30 ± 333.47 ND ND 802.83 ± 2243.38
aMethod: multi-mycotoxins analysis (aflatoxins B1, B2, G1, G2, and total aflatoxins) using liquid chromatography with tandem mass spectrometry (LC-MS/MS) (in- house method SOP No. LBLC-18004 based on QuEChERS method); limit of detection (LOD) = 0.25; limit of quantification (LOQ) = 0.50; ND (not detected) bData were generated from this study by the Philippine Food Safety Risk Profiling Project (PRPP) in 2019
cConcentrations less than the LOQ (0.50 µg/kg)
dMaximum level (ML) of aflatoxin in peanuts intended for processing set by the Codex Alimentarius Commission (CXS 193-1995 e. 2019) and adopted by the Philippine National Standard on the Code of Practice for the Prevention (PNS/BAFS 175:2015)
ePeanuts available from one seller were in undried and unshelled form, which were cabinet-dried and manually shelled prior to analysis fPeanuts available from one seller were in dried and unshelled form, which were manually shelled prior to analysis
Since AFL contamination can occur during crop growth and development or during storage, processing, packaging, and distribution, plus poor pre- and post-harvest practices may contribute to high incidences of AFL contamination in peanuts (Bediako et al. 2019; Spanjer 2019). It was reported in the Ilocos and Cagayan Valley raw peanut value chain analysis conducted by the Philippine Rural Development Project that there are still farmers who harvest prematurely, resulting in shriveled and poor- quality peanuts (DA 2014). Harvesting premature pods may not only affect the physical quality of the peanuts, but it may also reflect high levels of AFL according to the Codex Code of Practice for the Prevention and Reduction of Aflatoxin Contamination in Peanuts (CAC/
RCP 55-2004) (CAC 2004b). Some of the peanut samples already showed visible manifestations of mold growth characterized by discolored kernels upon collection from the peanut farmers and traders, which is an indicator of a significant risk of contamination by AFLs (Spanjer 2019).
The presence of mold may indicate insufficient drying of the peanut kernels and poor storage conditions. Gathered information on the survey of practices also showed that there was limited awareness of mycotoxin and AFL by the peanut stakeholders.
Overseas data based on several international AFL occurrence studies in Asia on AFL levels of peanut ranged from no detection (ND) to 1,602.5 µg/kg, with
mean AFL levels ranging from 0.55–51.71 µg/kg (Table 5). In comparison, peanut samples from Thailand had the highest mean AFL level at 51.71 µg/kg, which also exceeded the regulatory ML. According to the WHO and FAO (2017), reports showed that there was an extremely high AFL contamination in peanuts in the markets of developing countries, which corresponds to the results of these occurrence studies. Moreover, Thailand and the Philippines are both tropical countries with hot and humid climates, which are factors for AFL growth (FAO 1993; FAO-IAEA 2001; Tulayakul and Sugita-Konishi 2017). Thus, the high presence of AFL in peanuts in both countries may be attributed to this factor.
In a Taiwanese study conducted by Lien et al. (2019), imported peanuts and peanut products from the Philippines had a mean AFL level of 1.05 µg/kg (n = 109) with a maximum AFL level of 14.2 µg/kg, which were within Taiwan’s regulatory limit of 15 µg/kg. These values were also relatively lower compared to the AFL levels detected from the peanut and peanut product samples of the local occurrence studies in the Philippines. This shows that peanuts and peanut products exported outside the country are compliant with international standards and are of better quality, compared to the locally available ones in the Philippine market. These also show that AFL contamination in peanuts in the country remains a concern, which must be addressed for the safety of Filipino consumers.
Table 4. Aflatoxin levels (µg/kg) in peanut from studies in the Philippines.
Author
(year) Food source Type of
aflatoxin Method of analysis
No. of samples
lyzedana-
positive % samples
Aflatoxin level
(µg/kg) Limit of
detection (µg/kg)
Min Max Mean Max
leveli Bulatao-Jayme et al.a
(1982) Peanuts and peanut products except
peanut butter
AFB1
and B2 Rapid quantitative
TLC
630 70 NR NR 49.1 15 5
Garciab
(1989) Peanuts, raw (regu-
lar outlets) AFB1 NR 98 57 < 3 2,888 NR NR
Peanuts, raw (re-
gional) AFB1 205 48 < 3 600 NR NR
Galvez et al.c
(2003) Peanuts and peanut
products AFT TLC 105 NR ND 16,000e 1,467.58f 1
Rustia et al.g
(2011) Peanuts and peanut
products NR TLC 88 5.68h < 5 415 NR < 5
NR – not reported; ND – none detected; TLC – thin layer chromatography
aData from Bulatao-Jayme et al. (1982) with the main objective of establishing a possible relationship in humans between aflatoxin ingestion and the development of primary liver cancer, wherein a Philippine table of aflatoxin values of various food items was generated through analysis
bData from the [unpublished] FNRI surveillance from 1967–1982 which aimed to determine the presence of aflatoxin in various food items, as cited in Garcia (1989) cData from the study of Galvez et al. (2003) with the objective of developing a technology for the manual sorting of peanut kernels to eliminate aflatoxin contamination;
aflatoxin levels of dry-blanched peanut samples obtained during the development of the sorting process and during the pilot-scale and commercial-scale trials eFrom dry-blanched, discolored, and damaged sorted peanuts
fCalculated based on data presented within the study
gData from the occurrence and level of aflatoxin, 2004–2011, from Rustia et al. (2011) with an objective of discussing the present status of aflatoxin contamination occurrence in Philippine foods
hPercentage of samples > 20 µg/kg
iMaximum Level for total aflatoxin in peanuts intended for further processing (CXS 193-1995 e. 2019, cited by PNS/BAFS 175:2015)
Consumption information to establish baseline DE estimate. Table 8 shows the consumption data of peanuts in the Philippines from various available sources, particularly the FAO/WHO Food Safety Collaborative platform (FOSCOLLAB) and the DOST-FNRI, which ranged from 1.11–131.2 g/d. The FAO/WHO FOSCOLLAB is a global collaborative platform that integrates different sources of reliable data and information on food and chemical risks such as the JECFA database, the GEMS/
Food Contaminants database, the FAO/WHO Chronic Individual Food Consumption database (CIFOCOss), the WHO Collaborating Centers Database, and data from other United Nations (UN) organizations (FOSCOLLAB 2018). Among the consumption data gathered, the disaggregated food consumption data from the 2013 National Nutrition Survey (NNS) from the DOST-FNRI (notarized 2020, pers. comm.) was used in this risk profile. The DOST-FNRI has the authority to conduct NNSs, which provide a key source of data on food, health, and nutrition for the Philippine national government in response to their mandate to define the nutritional status of the Filipino citizens (EO 128 sec. 22, cited by DOST- FNRI 2015). Likewise, the WHO (2020) recommends that
national authorities conducting their own DE assessment use national food consumption and concentration data while applying international nutritional and toxicological reference values.
Comparison of Philippine DE estimates with overseas estimates. In this study, it was assumed in the calculation of DE estimates (in terms of EDI) that all Filipinos consume the same mean one-day per capita food consumption to establish a conservative estimate. A summary of the calculated EDI for the mean and 97.5th percentile of the Filipino adult (20–59 yr old) consuming population to AFB1, AFB2, AFG1, AFG2, and AFT in peanut in the Philippines using the consumption data from the Philippine DOST-FNRI (notarized 2020, pers. comm.), as well as the mean bw of the adult Asian population, was shown in Table 6.
The calculated EDI of the consuming population to AFT and AFB1 in peanuts ranged from 0.28–1,517.37 ng/kg bw/d and 0.28–1,295.99 ng/kg bw/d, respectively. At 97.5th percentile consumption, the calculated DE estimates of the Filipino adult (20–59 yr old) consuming population to AFT and AFB1 in peanut are 1.22–6,527.18 ng/kg
Table 5. Occurrence and level of total aflatoxins (AFT) in raw peanuts in Asia based on different international studies.
Area/ country/
place of study Year con-
ducted Method of analysis
Contaminat- ed samples/
number of samples
Percentage of positive samples(%)
Aflatoxin level
(μg/kg) Reference
Min Max Mean Max
levele Punjab, Pakistan 2013 HPLC–fluores-
cence detection 13/22a
16/29b 59.09
65.52 LODc LODc 59.8
82.1 6.4 ± 3.4 9.6 ± 2.5
15
Iqbal et al. (2013) Liaoning, China
2010-
2013 HPLC–fluores- cence detection
20/408 4.90 0.05 144.0 0.55 ± 7.80
Wu et al. (2016)
Henan, China 226/1190 19.00 0.06 1023.20 9.43 ± 54.98
Sichuan, China 71/455 15.60 0.24 1602.5 18.19 ±
100.38 Guangdong,
China 63/441 14.29 0.06 373.69 5.34 ± 32.90
Bangkok,
Thailand 2013- 2014
HPLC–fluores- cence detection
using AflaTest
column 16/20 80
NDd 303.55 47.11
Kooprasertying et al. (2016) HPLC–fluores-
cence detection using KU-AF02
IAC (in-house method)
NDd 359.29 51.71
Districts of Sa- na’a, Al-Hodei- da, and Aden,
Yemen
Not spec-
ified ELISA 76/89 85.39 1.00 44.2 9.72 ± 1.22 Murshed et al.
(2019)
aRaw peanut with shell bRaw peanut without shell cLOD – limit of detection dND – not detected
eMaximum level for total aflatoxin in peanuts intended for further processing (CXS 193-1995 e. 2019, cited by PNS/BAFS 175:2015)
bw/dand 1.22–5,574.90 ng/kg bw/d, respectively, which exceeded the recommended PMTDI of 1 ng/kg bw/d. The EDI values prove that AFB1 is the major contributor to AFT exposure, which accounts for 85.14% of Filipino adult AFT exposure in peanuts. In addition, maximum AFL levels from the generated concentration data were considered extremely high as compared to the Philippine regulatory limit or ML of 15 µg/kg. Thus, the calculated EDI values for the maximum values of AFB1, AFB2, and AFT exceed the recommended PMTDI of the consuming population by more than 100%. Therefore, the findings of this study based on the assumptions made indicate that the general adult Filipinos have a high risk of exposure to AFL in peanuts.
Several international studies have also been conducted to estimate and assess DE to AFLs in countries including Malaysia, Brazil (State of Parana), Vietnam, Malaysia, and Indonesia, as summarized in Table 7. Differences in these exposure estimates demonstrate that AFL contamination varies by location. When compared with the overseas DE estimates, the calculated mean DEs for AFT and AFB1 in the Philippines (1915.14 and 1,630.55 ng/kg bw/d, respectively) are relatively high.
Estimate of risk for the Philippines. To estimate the health risks of exposure of adult Filipinos to AFL from consumption of peanuts, the PMTDI was used as a basis and the MOE was also utilized. The EDI of the Filipino adult (20–59 yr old) high consuming population (consumption of 131.2 g peanuts/d), as discussed, was higher than the PMTDI, indicating an appreciable risk
to the health of the Filipino adult consuming population due to consumption of peanuts contaminated with AFL.
Furthermore, the EDI values according to AFL level distribution (minimum, maximum, and mean AFL levels, as well as the ML) were used to perform risk assessment using the MOE approach. Only the EDI values for AFB1 and AFT were used for the MOE calculation since the reference point, the BMDL10 value, was derived from a dose-response study of AFB1 in male Fischer rats and in reference to the MOE estimation performed by the EFSA in 2007.
Figures 1 and 2 present the MOE values for AFB1 and AFT exposures, respectively, due to peanut consumption of Filipino adults using the calculated EDI values based on the consumption data from the DOST-FNRI 2013 NNS: [a] mean and [b] 97.5th percentile consumption), and the FOSCOLLAB: [c] mean consumption. The MOE values calculated from the minimum exposure of peanut consumption from the FOSCOLLAB data were above the safe margin of 10,000 with an MOE value of 16,516.52 for both AFB1 and AFT. However, all MOE values for both AFB1 and AFT obtained using the DOST-FNRI consumption data of peanuts were below the safe margin of 10,000. Moreover, the MOE values were even below 1,000. Similar results were also obtained from the mean and maximum exposure of peanut consumption from the FOSCOLLAB data, wherein the MOE values were far below the safe margin of 10,000, which indicates a public health concern and suggests prioritization of risk management actions (EFSA 2005). The results of this study also showed the importance of the dietary
Table 6. Estimated daily intake (EDI) of the Filipino adult (20–59 yr old) consuming population (mean and 97.5th Percentile) to aflatoxin in peanut (Arachis hypogaea L.) in the Philippines compared to the recommended PMTDI.
Mean
BWa Peanut consumptionb Aflatoxin levelc Estimated daily intake (EDI)d PMTDIe
(kg) (g/day) (μg/kg) (ng/kg bw/d) (ng/kg bw/d)
Mean 97.5th per-
centile Mean 97.5th percentile
55.0 30.5 131.2
Minimum AFB1
AFT 0.51
0.51 0.28
0.28 1.22
1.22 1
Maximum AFB1
AFT 2337.04
2736.24 1295.99
1517.37 5574.90
6527.18 1
Mean AFB1
AFT 683.54
802.84 379.05
445.19 1630.55
1915.14 1
CAC ML AFT 15 8.32 35.78 1
aMean body weight (bw) of the adult Asian population (WHO 2020)
bDisaggregated peanut consumption (mean and 97.5th percentile) of Filipino adult consuming population ages 20–59 yr old (n = 246) from the 2013 National Nutrition Survey (notarized 2020, pers. comm., DOST-FNRI)
cAflatoxin levels: minimum, maximum, and mean levels of aflatoxin from 50 samples obtained in specified provinces in Table 3, and maximum level of aflatoxin in peanut intended for processing at 15 μg/kg; Codex General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995 e. 2019) and as indicated in the Philippine National Standard on the Code of Practice for the Prevention and Reduction of Aflatoxin Contamination in Peanuts (PNS/BAFS 2015)
dCalculated dietary exposure in terms of probable daily intake (PDI) using Equation 1
eProvisional maximum tolerable daily intake (PMTDI), 1.0 ng/kg bw/d, recommended by Kuiper-Goodman (1995, 1998) for children and adults, not carriers of the hepatitis B virus [as cited in Magrine et al. (2011)]; value also used for estimating the cancer potency per 100,000 population for exposure to AFB1 (WHO and FAO 2017)
