Discussion on common problems after introducing "reduction factor" into different working hour systems in occupational exposure assessment in GBZ 2.1—2019 / 环境与职业医学

Occupational exposure limits for hazardous agents in the workplace—Part 1: Chemical hazardous agents (GBZ 2.1—2019) has been implemented since April 1, 2020. The document redefines the evaluation of occupational exposure by introducing a "reduction factor" to adjust the occupational exposure limits of chemical hazardous agents for long working hour systems to ensure a protection level reasonable for the workers and equivalent to conventional occupational exposure limits. This paper discussed common problems encountered in the context of using this adjustment strategy, such as the adjustment being unable to cover all working hours, and the adjustment of values of terms associated with occupational exposure limits. Corresponding solutions were proposed. Working cycle and average exposure time of each working cycle were introduced to evaluate the actual working hours of workers. Regarding involved terms, adjustments of their corresponding values were clarified according to their definitions and application scenarios. Examples were provided for occupational health service providers so that their occupational health practices could be carried out in a more scientific and reasonable manner.

Analysis and exposure evaluation of cadmium residues in different tissues of portunus and mantis shrimp / 上海预防医学

ObjectiveTo understand the concentration of heavy metal cadmium and cadmium in portunus and mantis shrimp， and to timely identify food safety problems and potential hazards. MethodsPortunus and mantis shrimp samples from different provinces were collected and categorized based on different regions and locations， and some samples were made from tissue parts. Graphite furnace atomic absorption spectrometry was used to detect cadmium items， the cadmium exposure of portunus and mantis shrimp was evaluated simultaneously ResultsThe detection rate of cadmium in 124 batches of portunus sold in Shanghai was 100% （124/124）， the detection rate of cadmium in 63 batches of mantis shrimp sold in the market was also 100% （63/63）. The cadmium content varied in different tissue parts， and the cadmium enrichment in hepatopancreas was the highest in the edible parts of portunus and mantis shrimp. The average detection value， 50th percentile value， 95th percentile value of cadmium in the hepatopancreas of portunus accounted for 52.64%， 49.28% and 98.65% of the PTMI， respectively. The average detection value， 50th percentile value and 95th percentile value of cadmium in the hepatopancreas of mantis shrimp accounted for 30.76%， 32.04% and 46.16% of the PTMI， respectively. ConclusionThe average residual levels of heavy metal cadmium in portunus and mantis shrimp are within the safe range.

Paralytic shellfish poisoning contamination status and dietary exposure assessment in coastal cities of China / 预防医学

@#Paralytic shellfish poisoning contamination is a threat to human health. Based on review of research articles pertaining to paralytic shellfish poisoning contamination in shellfishes and assessment of dietary exposure to paralytic shellfish poisoning in coastal cities of China from 2007 to 2022, the article describes the status of paralytic shellfish poisoning contamination, influencing factors and dietary exposure assessment in different sea areas of China (Bohai Sea, Huanghai Sea, East China Sea and South China Sea), and the relatively high-level contamination of paralytic shellfish poisoning in shellfishes is found to strongly correlate with red tides caused by season and water temperature in the Bohai Sea and South China Sea areas. Acute exposure assessment based on point estimate model is commonly used for assessment of dietary exposure to paralytic shellfish poisoning, and the risk of human dietary exposure to paralytic shellfish poisoning is within the acceptable range in most areas. Intensified monitoring of paralytic shellfish poisoning contamination in shellfishes and full consideration of parameters like processing factor during dietary exposure assessment are required in the future to allow more precise results.

Benchmark dose estimation based on Bayesian model averaging and its application to evaluation of cadmium exposure of population in Baiyin / 环境与职业医学

Background The optimal model method for estimation of benchmark dose (BMD) does not consider the uncertainty of model selection. There is a lack of studies on using Bayesian model averaging (BMA) to estimate BMD. Objective To apply BMA to the exposure assessment of cadmium pollution in China, discuss the role of BMA in estimating BMD based on dose-response models, and to provide methodological support for health risk assessment of hazardous substances. Methods The parameters of five dose-response models (Gamma, Log-logistic, Log-probit, Two-stage, and Weibull models) estimated from the data from a cadmium-contaminated area in Baiyin City of Gansu Province and the urinary cadmium ranges in five cadmium-contaminated areas in China were used to simulate the data of varied correct models with different numbers of dosage groups (5 and 8) and different sample sizes (50, 100, and 200), then the performance of BMA and traditional optimal model were compared. The case analysis used the cadmium exposure data in Baiyin, Gansu Province. All analyses set urinary cadmium as the indicator of cadmium exposure, the abnormal rate of β2-microglobulin as the effect indicator, and the benchmark response to 10%. The correct model (the model used when simulating data), optimal model [the model with smallest Akaike information criterion (AIC)], and BMA were used to estimate BMD and lower confidence limit of benchmark dose (BMDL); the BMDs, BMDLs, and relative deviations from different methods were compared. Results In the simulation study, with increasing sample size or the number of dosage groups, the intervals of the 5th percentile and the 90th percentile of BMD tended to be narrower; when the correct model was a single model, the relative deviation of BMD estimation by BMA was greater than that of the traditional optimal model; when the correct model was an equal weight mixed model, the relative deviation of BMD estimation by BMA was less than that by the traditional optimal model. For the data of cadmium-contaminated areas, the optimal model was a Log-probit model (AIC=1814.46), followed by a Log-logistic model (AIC=1814.57); the BMDs (BMDLs) estimated by the Log-probit model, the Log-logistic model, and BMA were 3.46 (2.68), 3.16 (2.33), and 2.92 (2.07) μg·g−1, respectively. Conclusion The traditional optimal model is still recommended when the correct model is known. However, when the dose-response relationship of a hazardous substance is uncertain or with different sources or exposure grouping, compared with the traditional optimal model, BMA theoretically provides more stable estimation of BMD and BMDL by considering multiple possible alternative models.

Dietary exposure assessment of chlorate in infant formula / 上海预防医学

ObjectiveTo investigate chlorate contamination level in infant formula sold in Shanghai， and to evaluate the dietary exposure risk to infants in Shanghai. MethodsWith the risk monitoring data of chlorate in infant formula sold in Shanghai in 2020， combined with the dietary consumption data of infants， the dietary exposure of chlorate in infant formula was assessed via the point assessment method. ResultsIn 2020， the overall detection rate of chlorate in 120 infant formula samples was 98.3% （118/120）， the mean content was 124.5 μg⋅kg-1， the 50 percentile value was 64.6 μg⋅kg-1， and the maximum value was 1 475.0 μg⋅kg-1. The mean and 95 percentile value of daily chlorate intake from infant formula for infants aged 0‒36 months in Shanghai were 1.10 and 1.84 μg⋅kg-1， accounting for 36.7% and 61.3% of the tolerable daily intake （TDI） of chlorate （3μg⋅kg-1）， respectively. The mean， 50 percentile value and 95 percentile value of daily chlorate exposure of infants in different month-age groups （0‒6 months， 6‒12 months， 12‒36 months） through infant formula were lower than the TDI value. ConclusionThe health risk of daily chlorate intake from infant formula for infants and young children aged 0‒36 months in Shanghai is at an acceptable level.

Risk assessment of manganese in lip cosmetics / 上海预防医学

Objective:To determine the level of manganese and assess potential health risks of lip cosmetics. Methods:Assessment on manganese of lip cosmetics was performed using high-end exposure analysis mode based on the daily dosage. Results:In a total of 264 lip cosmetics samples， manganese was detected in the 249 sample， with a detection rate of 94.3%. Daily exposure was determined to be 3.88×10-5 mg/kg. Safety margin was 3 608 and safety limit was 45 mg/kg. Conclusion:Level of manganese in lip cosmetics remains safe. Health risk is low when appropriately used according to the daily usage. However， it is noted that level of manganese exceeds the limits in approximately 10% of the samples， posing a potential health threat.

An investigation on aluminum content in commercially available flour products and risk assessment of dietary aluminum exposure of population in Minhang District, Shanghai / 公共卫生与预防医学

Objective To investigate aluminum content in commercially available flour products in Minhang District, Shanghai, and to assess the risk of dietary aluminum exposure among permanent residents in Minhang. Methods From 2018 to 2019, a total of 227 samples including fried flour products, steamed flour products, puffed products and baked flour products, were collected in Minhang District to detect the aluminum content. The food frequency table was used to investigate the consumption of flour foods by permanent residents in Minhang District and to assess population dietary aluminum exposure risk. Results The average content of aluminum in 227 kinds of flour products was 31.66 mg/kg, and the exceeding standard rate was 3.96%. The over-standard foods were all fried flour products, and the over-standard rate reached 10.47%. Moreover, the aluminum over standard rate of flour products produced by itinerant vendors and restaurants was significantly higher than that of flour products produced by supermarkets and manufacturers. The average dietary intake of aluminum in Minhang residents was 0.18 mg/kg per week, accounting for 9.03% of the provisional tolerable weekly intake (PTWI). The aluminum exposure of the population with high consumption of foods was 1.4 mg/kg per week, accounting for 69.90% of the PTWI. Among the four types of flour products, fried flour products had the highest contribution rate to aluminum exposure. The daily consumption of fried flour products in males was significantly higher than that in females (P<0.05), and the 18-34 age group was significantly higher than the 60 years old and above group (P<0.05). Conclusion The risk of the average dietary aluminum exposure of flour foods among Minhang residents is relatively low, but people with high consumption of foods would be confronted with increased health risks. It is necessary to strengthen the supervision on the use of aluminum-containing additives in itinerant vendors and restaurants, and actively advocate reducing the frequency and the consumption of fried flour products, thus reduce the exposure to the high risk of dietary aluminum in fried flour products

Dietary exposure assessment of phthalic acid esters in Guangzhou residents / 公共卫生与预防医学

Objective To understand phthalic acid esters pollution of daily consumed food in Guangzhou City，and evaluate the hazard of phthalic acid esters exposure in residents dietary. Methods Detected the content of phthalic acid esters in 10 types of food by gas chromatography-mass spectroscopy（GC-MS）methods .It combined with a survey on dietary nutrients intake of Guangzhou residents was conducted．Hazard index on the dietary exposure assessment of chemicals in food was applied. Results It showed that the highest levels of DBP，DEHP and DIBP，from the mixed diet samples in Guangzhou were 1.256，1.418，0.576 mg/kg respectively；and the exposure level of DBP，DEHP and DIBP were 2.431、5.981、2.408μg/kg.d ;HQ was respectively 0.243、0.125、0.025. HI was 0.393. Conclusion The dietary contamination of phthalic acid esters for Guangzhou was kept at a low level.But the pollution of 3 kinds of mixed samples such as meats，eggs，aquatic and products may be a certain risk of health that should attract more attention.

Levels of BPA in makdous, a traditional Syrian food, using solid-phase extraction followed by HPLC

Bisphenol A (BPA), an endocrine disrupter, can migrate from packaging material into food stuff. This research was designed to measure BPA levels in makdous, a traditional Syrian food. Forty three samples of makdous stored in different plastic containers (polyethylene (PE), polypropylene (PP), and unspecified plastic containers) were analyzed every 3 months for one year beginning July 2017. Quantification of BPA was carried out by an RP-HPLC system equipped with fluorescence detector after solid phase extraction. Migration was found in PE and PP plastic containers with slight differences. Statistically significant differences in BPA levels were observed between samples assayed after two weeks of preparation and samples assayed after 12 months (mean 16.32 vs. 38.26 µg/kg, p value=0.003). According to these amounts, BPA levels were all under the specific migration limit of 0.05 mg/kg as newly referred in Regulation (EU) No 2018/213. These levels of exposure would only contribute to 2.15% and 2.75% of the EFSA t-TDI in both men and women respectively based on mean dietary exposure estimates derived from a 24-h dietary information study from 875 participants. Hence there are no concerns about potential health risks from makdous consumption

Dermal Exposure to Pesticides among Sprayers in Different Agriculture Subsectors in Malaysia: Observational Method using DREAM

Abstract@#Introduction: An assessment of dermal exposure to pesticide mixtures among sprayers was made as a function of crop type, in four agricultural subsectors in Malaysia. Methods: The potential and actual dermal exposures for 160 pesticide sprayers performing pesticide spraying task were estimated by using Dermal Exposure Assessment Method (DREAM). Results: Results showed that there was significant difference between nationality (p<0.001), highest education (p<0.001), monthly income (p=0.002), body mass index (p<0.001) and smoking habit (p<0.001) distributions of sprayers in different agriculture subsectors. Various types of pesticides were used by respondents, where class II (moderately hazardous) and class III (slightly hazardous) pesticides were the most frequently used pesticides. There was a significant difference in both tPDE (χ2 = 118.093, p<0.001) and tADE (χ2 = 84.980, p<0.001) between different agricultural sectors, where the prominent high tPDE was observed among paddy pesticide sprayers (151.39 ± 22.64 DU) while lowest exposure was recorded among oil palm plantation sprayers (47.67 ± 18.47 DU). Conclusion: Based on DREAM exposure categories, majority of the pesticide sprayers (68.9%) working in paddy farming were exposed in low dermal exposure while 26.7% of respondents were exposed to moderate exposure. Pesticide sprayers in other agriculture sectors were exposed to very low to low exposure level. Dermal exposure distributions on body parts were varied between sectors, influenced by several factors such as crop type, height, and spraying methods.

Occupational Risk Factors for Prostate Cancer: A Meta-analysis

Prostate cancer is the second most common cancer in men worldwide. There are many occupational factors that have been suggested to cause prostate cancer. Our aim was to evaluate the evidence for causality by a literature review of occupational factors. We searched literature in Medline and SCOPUS from 1966 to June 30, 2015 to identify occupational risk factors for prostate cancer. The following risk factors were selected: farmers/agricultural workers, pesticides – whole group, and separately organophosphate and organochlorine pesticides, carbamates and triazines, cadmium, chromium, cutting fluids, acrylonitrile, rubber manufacturing, whole body vibration, shift work, flight personnel, ionizing radiation, and occupational physical activity. For each factor a literature search was performed and presented as meta-analysis of relative risk and heterogeneity (Q and I² index). A total of 168 original studies met the inclusion criteria with 90,688 prostate cancer cases. Significantly increased risks were observed for the following occupational exposures: pesticides (metaRR = 1.15, 95% confidence interval [CI] = 1.01–1.32; I² = 84%), and specifically group of organochlorine pesticides (meta relative risk [metaRR] = 1.08, 95% CI = 1.03–1.14; I² = 0%), chromium (metaRR = 1.19, 95% CI = 1.07–1.34; I² = 31%), shift work (metaRR = 1.25, 95% CI = 1.05–1.49; I² = 78%) and pilots (metaRR = 1.41, 95% CI = 1.02–1.94; I² = 63%) and occupational physical activity in cohort studies (metaRR = 0.87, 95% CI = 0.81–0.94; I² = 0%). The literature review supports a causal association for a few of the previously suggested factors.

Review of survey method for human time-activity pattern and its application in the exposure assessment of air pollutants / 中华预防医学杂志

Time activity pattern refers to the time and behavior of people at different locations. The knowledge of time-activity pattern is essential for air pollution exposure assessment when direct personal exposure monitoring can't not be conducted, because air pollutant concentrations may vary significantly by location and activity. This review is focused on the survey method for human time-activity pattern and its application in the exposure assessment of air pollutants. After comparing the diary-reported trips and Global Positioning System (GPS) recording method, we believed that diary-reported trips were more reliable in describing comprehensive and detail records of the behavior and environmental circumstances while GPS-recorded trend to maintain sound information of time, location and transportations. Meanwhile, according to different subjects, the air pollution exposure model could be divided for population and individuals. There were great difference between two types of model in many areas, including the required information about time, activity and microenvironment.

Expert clinician's perspectives on environmental medicine and toxicant assessment in clinical practice

BACKGROUND@#Most clinicians feel ill-equipped to assess or educate patients about toxicant exposures, and it is unclear how expert environmental medicine clinicians assess these exposures or treat exposure-related conditions. We aimed to explore expert clinicians' perspectives on their practice of environmental medicine to determine the populations and toxicants that receive the most attention, identify how they deal with toxicant exposures and identify the challenges they face and where they obtain their knowledge.@*METHODS@#A qualitative study involving semi-structured interviews with expert environmental clinicians in Australia and New Zealand was conducted. Interviews were recorded and transcribed, and themes were identified and collated until no new themes emerged.@*RESULTS@#Five dominant themes emerged from 16 interviews: (1) environmental medicine is a divided profession based on type of practice, patient cohort seen and attitudes towards nutrition and exposure sources; (2) clinical assessment of toxicant exposures is challenging; (3) the environmental exposure history is the most important clinical tool; (4) patients with environmental sensitivities are increasing, have unique phenotypes, are complex to treat and rarely regain full health; and (5) educational and clinical resources on environmental medicine are lacking.@*CONCLUSIONS@#Environmental medicine is divided between integrative clinicians and occupational and environmental physicians based on their practice dynamics. All clinicians face challenges in assessing toxicant loads, and an exposure history is seen as the most useful tool. Standardised exposure assessment tools have the potential to significantly advance the clinical practice of environmental medicine and expand its reach across other clinical disciplines.

Evaluation of the Exposure to Environmental Pollutants Emanating from National Industrial Complexes

The industrial complexes built during the course of economic development in South Korea played a pivotal role in the country's rapid economic growth. However, this growth was accompanied by health problems due to the pollutants released from the industrial complexes inevitably located near residential areas, given the limited land area available in South Korea. This study was conducted to evaluate the exposure to each pollutant emanating from industrial complexes for residents living in nearby areas, and to determine the substances requiring priority attention in future surveys. Pollutants were comprehensively categorized according to their emission and exposure levels based on data previously collected from the study areas. The emission, ambient concentration, and biomarker concentration levels of major pollutants emitted from eight national industrial complexes (Ulsan, Pohang, Gwangyang, Yeosu, Chungju, Daesan, Sihwa, and Banwol) were determined and tabulated. Each of the values was compared with the national/local average values, reference values, or control area concentrations depending on availability. Substances with completed exposure pathways and with high values for emissions, ambient concentrations, and biomarker concentrations were considered the substances posing exposure risks to the residents living near the corresponding industrial complex. The substances requiring continuous monitoring or supplementary exposure investigation were also categorized and presented. Lead and benzene had higher values for emissions, ambient concentrations, and biomarker concentrations in the Ulsan Industrial Complex area; thus, they were most likely to pose exposure risks to residents living in the area's neighborhoods. In other areas, styrene, xylene, cadmium, nitrogen oxide, trichloroethylene, nickel, manganese, and chromium required continuous monitoring, and arsenic, nickel, manganese, and chromium required biomarker measurements. In conclusion, the substances identified and categorized in this study need to be given appropriate attention in future surveys on exposure risks and health effects related to industrial complexes.

Review for Retrospective Exposure Assessment Methods Used in Epidemiologic Cancer Risk Studies of Semiconductor Workers: Limitations and Recommendations

This article aims to provide a systematic review of the exposure assessment methods used to assign wafer fabrication (fab) workers in epidemiologic cohort studies of mortality from all causes and various cancers. Epidemiologic and exposure–assessment studies of silicon wafer fab operations in the semiconductor industry were collected through an extensive literature review of articles reported until 2017. The studies found various outcomes possibly linked to fab operations, but a clear association with the chemicals in the process was not found, possibly because of exposure assessment methodology. No study used a tiered assessment approach to identify similar exposure groups that incorporated manufacturing era, facility, fab environment, operation, job and level of exposure to individual hazardous agents. Further epidemiologic studies of fab workers are warranted with more refined exposure assessment methods incorporating both operation and job titleand hazardous agents to examine the associations with cancer risk or mortality.

Evaluation of the Exposure to Environmental Pollutants Emanating from National Industrial Complexes

The industrial complexes built during the course of economic development in South Korea played a pivotal role in the country's rapid economic growth. However, this growth was accompanied by health problems due to the pollutants released from the industrial complexes inevitably located near residential areas, given the limited land area available in South Korea. This study was conducted to evaluate the exposure to each pollutant emanating from industrial complexes for residents living in nearby areas, and to determine the substances requiring priority attention in future surveys. Pollutants were comprehensively categorized according to their emission and exposure levels based on data previously collected from the study areas. The emission, ambient concentration, and biomarker concentration levels of major pollutants emitted from eight national industrial complexes (Ulsan, Pohang, Gwangyang, Yeosu, Chungju, Daesan, Sihwa, and Banwol) were determined and tabulated. Each of the values was compared with the national/local average values, reference values, or control area concentrations depending on availability. Substances with completed exposure pathways and with high values for emissions, ambient concentrations, and biomarker concentrations were considered the substances posing exposure risks to the residents living near the corresponding industrial complex. The substances requiring continuous monitoring or supplementary exposure investigation were also categorized and presented. Lead and benzene had higher values for emissions, ambient concentrations, and biomarker concentrations in the Ulsan Industrial Complex area; thus, they were most likely to pose exposure risks to residents living in the area's neighborhoods. In other areas, styrene, xylene, cadmium, nitrogen oxide, trichloroethylene, nickel, manganese, and chromium required continuous monitoring, and arsenic, nickel, manganese, and chromium required biomarker measurements. In conclusion, the substances identified and categorized in this study need to be given appropriate attention in future surveys on exposure risks and health effects related to industrial complexes.

Evidence of the Possible Harm of Endocrine-Disrupting Chemicals in Humans: Ongoing Debates and Key Issues

Evidence has emerged that endocrine-disrupting chemicals (EDCs) can produce adverse effects, even at low doses that are assumed safe. However, systemic reviews and meta-analyses focusing on human studies, especially of EDCs with short half-lives, have demonstrated inconsistent results. Epidemiological studies have insuperable methodological limitations, including the unpredictable net effects of mixtures, non-monotonic dose-response relationships, the non-existence of unexposed groups, and the low reliability of exposure assessment. Thus, despite increases in EDC-linked diseases, traditional epidemiological studies based on individual measurements of EDCs in bio-specimens may fail to provide consistent results. The exposome has been suggested as a promising approach to address the uncertainties surrounding human studies, but it is never free from these methodological issues. Although exposure to EDCs during critical developmental periods is a major concern, continuous exposure to EDCs during non-critical periods is also harmful. Indeed, the evolutionary aspects of epigenetic programming triggered by EDCs during development should be considered because it is a key mechanism for developmental plasticity. Presently, living without EDCs is impossible due to their omnipresence. Importantly, there are lifestyles which can increase the excretion of EDCs or mitigate their harmful effects through the activation of mitohormesis or xenohormesis. Effectiveness of lifestyle interventions should be evaluated as practical ways against EDCs in the real world.

Urinary Trans, Trans-Muconic Acid is Not a Reliable Biomarker for Low-level Environmental and Occupational Benzene Exposures

BACKGROUND: Benzene is a known occupational and environmental pollutant. Its urinary metabolite trans, trans-muconic acid (tt-MA) has been introduced by some environmental and occupational health regulatory associations as a biological index for the assessment of benzene exposure; however, recently, doubts have been raised about the specificity of tt-MA for low-level benzene exposures. In the present study, we investigated the association between urinary levels of tt-MA and inhalational exposure to benzene in different exposure groups. METHODS: Benzene exposure was assessed by personal air sampling. Collected benzene on charcoal tube was extracted by carbon disulfide and determined by a gas chromatograph (gas chromatography with a flame ionization detector). Urinary tt-MA was extracted by a strong anion-exchange column and determined with high-performance liquid chromatography–UV. RESULTS: Urinary levels of tt-MA in intensive benzene exposure groups (chemical workers and police officers) were significantly higher than other groups (urban and rural residents), but its levels in the last two groups with significant different exposure levels (mean = 0.081 ppm and 0.019 ppm, respectively) showed no significant difference (mean = 388 μg/g creatinine and 282 μg/g, respectively; p < 0.05). Before work shift, urine samples of workers and police officers showed a high amount of tt-MA and its levels in rural residents’ samples were not zero. CONCLUSION: Our results suggest that tt-MA may not be a reliable biomarker for monitoring low-level (below 0.5 ppm) benzene exposures.

Perchlorate contamination exposure assessment on commercial foods in Shanghai / 上海预防医学

Objective To ascertain the perchlorate contamination level in commercial foods and health risks so as to provide reference for perchlorate standard formulation and risk management.Methods Perchlorate risk survey was done on commercial foods in Shanghai;in combination with the survey results of residents'' food consumption,the exposure assessment on the presence of perchlorate in commercial food was performed by probability assessment approach.Results A total of 80 food samples from 8 food categories were analyzed,including grain,vegetables,fruits,dairy products,meat,eggs,aquatic products and teaand perchlorate detection rate was 78.8% with a mean value as 13.0±26.4 μg/kg.The highest mean value of perchlorates was 59.0±51.9 μg/kg in tea,and the lowest mean value was 3.4±2.3 μg/kg in fruits.With protection of human life and health as the maximum principle (there were supposed to be no losses of perchlorate during food processing),it was found that the estimated average dietary intake of perchlorate from the 8 food categories was 0.25 μg/kgbw.However,the 95 percentile exposure estimates reached up to 0.44 μg/kgbw,which exceeded the tolerable daily intake value of 0.3μg/kgbw established by European Food Safety Authority for healthy adults.Therefore,potential health risk may exist to certain groups of people.Conclusion Due to its high water-solubility,degradation of perchlorate in food processing probably occurs to certain extent.Therefore,there is need to carry out further actual exposure study.

Association between Phthalate Exposure and the Use of Plastic Containers in Shanghai Adults / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Consuming phthalates may be due to the presence of food contact materials, such as plastic containers. In this study, we investigated the association between plastic container use and phthalate exposure in 2,140 Shanghai adults.</p><p><b>METHODS</b>Participants completed a questionnaire on the frequency of using plastic containers in different scenarios in the previous year (e.g., daily, weekly) and on the consumption of plastic-packaged foods in the previous three days (yes or no). Urinary phthalate metabolites were used to assess the association between phthalate exposure and the use of plastic containers.</p><p><b>RESULTS</b>The metabolites of di-(2-ethylhexyl) phthalate (DEHP) were the most frequently detected in urine. The results revealed that phthalate exposure was associated with consumption of plastic-packaged breakfast or processed food items in the previous three days. The consumption of these two food items had strong synergistic effects on increasing urinary concentrations of most phthalate metabolites.</p><p><b>CONCLUSION</b>Our results of plastic-packaged breakfast and processed food may be explained by the use of flexible plastic containers, indicating the importance of risk assessment for the application of flexible plastic containers.</p>