Background Chemical exposures have been associated with a variety of health effects; however, lit... more Background Chemical exposures have been associated with a variety of health effects; however, little is known about the global disease burden from foodborne chemicals. Food can be a major pathway for the general population's exposure to chemicals, and for some chemicals, it accounts for almost 100% of exposure. Methods and Findings Groups of foodborne chemicals, both natural and anthropogenic, were evaluated for their ability to contribute to the burden of disease. The results of the analyses on four chemicals are presented here-cyanide in cassava, peanut allergen, aflatoxin, and dioxin. Systematic reviews of the literature were
Nanoparticles (NP) have a tendency to agglomerate after dispersion in physiological media, which ... more Nanoparticles (NP) have a tendency to agglomerate after dispersion in physiological media, which can be prevented by the addition of serum. This may however result in modification of the toxic potential of particles due to the formation of protein corona. Our study aimed to analyze the role of serum that is added to improve the dispersion of 10 nm TiO2 NPs on in vitro and in vivo effects following the exposure via the respiratory route. We characterized NP size, surface charge, sedimentation rate, the presence of protein corona and the oxidant-generating capacity after NP dispersion in the presence/absence of serum. The effect of serum on NP internalization, cytotoxicity and pro-inflammatory responses was assessed in a human pulmonary cell line, NCI-H292. Serum in the dispersion medium led to a slower sedimentation, but an enhanced cellular uptake of TiO2 NPs. Despite this greater uptake, the pro-inflammatory response in NCI-H292 cells was lower after serum supplementation (used eit...
Background Chemical exposures have been associated with a variety of health effects; however, lit... more Background Chemical exposures have been associated with a variety of health effects; however, little is known about the global disease burden from foodborne chemicals. Food can be a major pathway for the general population's exposure to chemicals, and for some chemicals, it accounts for almost 100% of exposure. Methods and Findings Groups of foodborne chemicals, both natural and anthropogenic, were evaluated for their ability to contribute to the burden of disease. The results of the analyses on four chemicals are presented here - cyanide in cassava, peanut allergen, aflatoxin, and dioxin. Systematic reviews of the literature were conducted to develop age- and sex-specific disease incidence and mortality estimates due to these chemicals. From these estimates, the numbers of cases, deaths and disability adjusted life years (DALYs) were calculated. For these four chemicals combined, the total number of illnesses, deaths, and DALYs in 2010 is estimated to be 339,000 (95% uncertainty interval [UI]: 186,000-1,239,000); 20,000 (95% UI: 8,000-52,000); and 1,012,000 (95% UI: 562,000-2,822,000), respectively. Both cyanide in cassava and aflatoxin are associated with diseases with high case-fatality ratios. Virtually all human exposure to these four chemicals is through the food supply. Conclusion Chemicals in the food supply, as evidenced by the results for only four chemicals, can have a significant impact on the global burden of disease. The case-fatality rates for these four chemicals range from low (e.g., peanut allergen) to extremely high (aflatoxin and liver cancer). The effects associated with these four chemicals are neurologic (cyanide in cassava), cancer (aflatoxin), allergic response (peanut allergen), endocrine (dioxin), and reproductive (dioxin).
Health impact assessments (HIA) have become an important tool for applying evidence-based policy.... more Health impact assessments (HIA) have become an important tool for applying evidence-based policy. Recently, the concept of HIA has been introduced in the field of chemical substances. Two main issues are encountered, i.e., the focus of risk assessment is deriving safe levels and on first signs of adverse effects. These adverse effects, often at a subclinical level, fall outside the scope of a HIA. However, the number of subjects with subclinical effects can be extensive, thus relevant to consider in HIA and subsequent risk management policies and socioeconomic analyses (e.g., under REACH). The approach to include subclinical effects in a HIA relies on the dose–response relationship for toxicological endpoints, which are indicative for subclinical and clinical effects. Assessment of (sub)clinical effect sizes requires expertise from toxicologists, pathologists, and risk assessors. The clinical effect is appraised by a disability weight in the disability adjusted life year (DALY) conc...
This study uniquely describes all steps of the risk assessment process for the use of one specifi... more This study uniquely describes all steps of the risk assessment process for the use of one specific nanomaterial (nanosilica) in food products. The aim was to identify gaps in essential knowledge and the difficulties and uncertainties associated with each of these steps. Several food products with added silica (E551) were analyzed for the presence, particle size and concentration of nanosilica
Journal of exposure science & environmental epidemiology, Jan 29, 2014
As personal care products (PCPs) are used in close contact with a person, they are a major source... more As personal care products (PCPs) are used in close contact with a person, they are a major source of consumer exposure to chemical substances contained in these products. The estimation of realistic consumer exposure to substances in PCPs is currently hampered by the lack of appropriate data and methods. To estimate aggregate exposure of consumers to substances contained in PCPs, a person-oriented consumer exposure model has been developed (the Probabilistic Aggregate Consumer Exposure Model, PACEM). The model simulates daily exposure in a population based on product use data collected from a survey among the Dutch population. The model is validated by comparing diethyl phthalate (DEP) dose estimates to dose estimates based on biomonitoring data. It was found that the model's estimates compared well with the estimates based on biomonitoring data. This suggests that the person-oriented PACEM model is a practical tool for assessing realistic aggregate exposures to substances in PC...
This study uniquely describes all steps of the risk assessment process for the use of one specifi... more This study uniquely describes all steps of the risk assessment process for the use of one specific nanomaterial (nanosilica) in food products. The aim was to identify gaps in essential knowledge and the difficulties and uncertainties associated with each of these steps. Several food products with added silica (E551) were analyzed for the presence, particle size and concentration of nanosilica particles, using experimental analytical data, and the intake of nanosilica via food was estimated. As no information is available on the absorption of nanosilica from the gastrointestinal tract, two scenarios for risk assessment were considered. The first scenario assumes that the silica is absorbed as dissolved silica, while the second scenario assumes that nanosilica particles themselves are absorbed from the gastrointestinal tract. For the first scenario no adverse effects are expected to occur. For the second scenario there are too many uncertainties to allow proper risk assessment. Therefore, it is recommended to prioritize research on how nanosilica is absorbed from the gastrointestinal tract.
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, Jan 2, 2014
Exposures to plant protection products (PPPs) are assessed using risk analysis methods to protect... more Exposures to plant protection products (PPPs) are assessed using risk analysis methods to protect public health. Traditionally, single sources, such as food or individual occupational sources, have been addressed. In reality, individuals can be exposed simultaneously to multiple sources. Improved regulation therefore requires the development of new tools for estimating the population distribution of exposures aggregated within an individual. A new aggregate model is described, which allows individual users to include as much, or as little, information as is available or relevant for their particular scenario. Depending on the inputs provided by the user, the outputs can range from simple deterministic values through to probabilistic analyses including characterisations of variability and uncertainty. Exposures can be calculated for multiple compounds, routes and sources of exposure. The aggregate model links to the cumulative dietary exposure model developed in parallel and is imple...
Background Chemical exposures have been associated with a variety of health effects; however, lit... more Background Chemical exposures have been associated with a variety of health effects; however, little is known about the global disease burden from foodborne chemicals. Food can be a major pathway for the general population's exposure to chemicals, and for some chemicals, it accounts for almost 100% of exposure. Methods and Findings Groups of foodborne chemicals, both natural and anthropogenic, were evaluated for their ability to contribute to the burden of disease. The results of the analyses on four chemicals are presented here-cyanide in cassava, peanut allergen, aflatoxin, and dioxin. Systematic reviews of the literature were
Nanoparticles (NP) have a tendency to agglomerate after dispersion in physiological media, which ... more Nanoparticles (NP) have a tendency to agglomerate after dispersion in physiological media, which can be prevented by the addition of serum. This may however result in modification of the toxic potential of particles due to the formation of protein corona. Our study aimed to analyze the role of serum that is added to improve the dispersion of 10 nm TiO2 NPs on in vitro and in vivo effects following the exposure via the respiratory route. We characterized NP size, surface charge, sedimentation rate, the presence of protein corona and the oxidant-generating capacity after NP dispersion in the presence/absence of serum. The effect of serum on NP internalization, cytotoxicity and pro-inflammatory responses was assessed in a human pulmonary cell line, NCI-H292. Serum in the dispersion medium led to a slower sedimentation, but an enhanced cellular uptake of TiO2 NPs. Despite this greater uptake, the pro-inflammatory response in NCI-H292 cells was lower after serum supplementation (used eit...
Background Chemical exposures have been associated with a variety of health effects; however, lit... more Background Chemical exposures have been associated with a variety of health effects; however, little is known about the global disease burden from foodborne chemicals. Food can be a major pathway for the general population's exposure to chemicals, and for some chemicals, it accounts for almost 100% of exposure. Methods and Findings Groups of foodborne chemicals, both natural and anthropogenic, were evaluated for their ability to contribute to the burden of disease. The results of the analyses on four chemicals are presented here - cyanide in cassava, peanut allergen, aflatoxin, and dioxin. Systematic reviews of the literature were conducted to develop age- and sex-specific disease incidence and mortality estimates due to these chemicals. From these estimates, the numbers of cases, deaths and disability adjusted life years (DALYs) were calculated. For these four chemicals combined, the total number of illnesses, deaths, and DALYs in 2010 is estimated to be 339,000 (95% uncertainty interval [UI]: 186,000-1,239,000); 20,000 (95% UI: 8,000-52,000); and 1,012,000 (95% UI: 562,000-2,822,000), respectively. Both cyanide in cassava and aflatoxin are associated with diseases with high case-fatality ratios. Virtually all human exposure to these four chemicals is through the food supply. Conclusion Chemicals in the food supply, as evidenced by the results for only four chemicals, can have a significant impact on the global burden of disease. The case-fatality rates for these four chemicals range from low (e.g., peanut allergen) to extremely high (aflatoxin and liver cancer). The effects associated with these four chemicals are neurologic (cyanide in cassava), cancer (aflatoxin), allergic response (peanut allergen), endocrine (dioxin), and reproductive (dioxin).
Health impact assessments (HIA) have become an important tool for applying evidence-based policy.... more Health impact assessments (HIA) have become an important tool for applying evidence-based policy. Recently, the concept of HIA has been introduced in the field of chemical substances. Two main issues are encountered, i.e., the focus of risk assessment is deriving safe levels and on first signs of adverse effects. These adverse effects, often at a subclinical level, fall outside the scope of a HIA. However, the number of subjects with subclinical effects can be extensive, thus relevant to consider in HIA and subsequent risk management policies and socioeconomic analyses (e.g., under REACH). The approach to include subclinical effects in a HIA relies on the dose–response relationship for toxicological endpoints, which are indicative for subclinical and clinical effects. Assessment of (sub)clinical effect sizes requires expertise from toxicologists, pathologists, and risk assessors. The clinical effect is appraised by a disability weight in the disability adjusted life year (DALY) conc...
This study uniquely describes all steps of the risk assessment process for the use of one specifi... more This study uniquely describes all steps of the risk assessment process for the use of one specific nanomaterial (nanosilica) in food products. The aim was to identify gaps in essential knowledge and the difficulties and uncertainties associated with each of these steps. Several food products with added silica (E551) were analyzed for the presence, particle size and concentration of nanosilica
Journal of exposure science & environmental epidemiology, Jan 29, 2014
As personal care products (PCPs) are used in close contact with a person, they are a major source... more As personal care products (PCPs) are used in close contact with a person, they are a major source of consumer exposure to chemical substances contained in these products. The estimation of realistic consumer exposure to substances in PCPs is currently hampered by the lack of appropriate data and methods. To estimate aggregate exposure of consumers to substances contained in PCPs, a person-oriented consumer exposure model has been developed (the Probabilistic Aggregate Consumer Exposure Model, PACEM). The model simulates daily exposure in a population based on product use data collected from a survey among the Dutch population. The model is validated by comparing diethyl phthalate (DEP) dose estimates to dose estimates based on biomonitoring data. It was found that the model's estimates compared well with the estimates based on biomonitoring data. This suggests that the person-oriented PACEM model is a practical tool for assessing realistic aggregate exposures to substances in PC...
This study uniquely describes all steps of the risk assessment process for the use of one specifi... more This study uniquely describes all steps of the risk assessment process for the use of one specific nanomaterial (nanosilica) in food products. The aim was to identify gaps in essential knowledge and the difficulties and uncertainties associated with each of these steps. Several food products with added silica (E551) were analyzed for the presence, particle size and concentration of nanosilica particles, using experimental analytical data, and the intake of nanosilica via food was estimated. As no information is available on the absorption of nanosilica from the gastrointestinal tract, two scenarios for risk assessment were considered. The first scenario assumes that the silica is absorbed as dissolved silica, while the second scenario assumes that nanosilica particles themselves are absorbed from the gastrointestinal tract. For the first scenario no adverse effects are expected to occur. For the second scenario there are too many uncertainties to allow proper risk assessment. Therefore, it is recommended to prioritize research on how nanosilica is absorbed from the gastrointestinal tract.
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, Jan 2, 2014
Exposures to plant protection products (PPPs) are assessed using risk analysis methods to protect... more Exposures to plant protection products (PPPs) are assessed using risk analysis methods to protect public health. Traditionally, single sources, such as food or individual occupational sources, have been addressed. In reality, individuals can be exposed simultaneously to multiple sources. Improved regulation therefore requires the development of new tools for estimating the population distribution of exposures aggregated within an individual. A new aggregate model is described, which allows individual users to include as much, or as little, information as is available or relevant for their particular scenario. Depending on the inputs provided by the user, the outputs can range from simple deterministic values through to probabilistic analyses including characterisations of variability and uncertainty. Exposures can be calculated for multiple compounds, routes and sources of exposure. The aggregate model links to the cumulative dietary exposure model developed in parallel and is imple...
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