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Abstract Although the systemic property of neonicotinoid (neonics) has become the most widely used insecticide worldwide since late 1990s, the current literature offers limited information about the human dietary intake and the potential risks of neonics. In this study, we aimed to assess the cumulative risk of total neonics intakes through fruit and vegetable consumption in 58 children ages 8–12 participated in the Hangzhou China (HZC) study over 5 consecutive weekends. Individual neonic residues in each food item were aggregated using the relative potency factor approach into a single metric (IMI RPF), representing dietary intakes of imidacloprid-equivalent total neonics. We then estimated the average daily intake (ADI) of total neonics through fruit and vegetable consumption and evaluated the cumulative dietary risk of neonics. All of the 123 samples were detected with at least one neonic. Commonly consumed foods, such as carrots, green vegetables, baby cabbage, and apple were found with more than 6 neonics. The estimated ADIs of total neonics vegetable and fruit consumption using the mean IMI RPF for apples and green vegetables, two most consumed food items, were 237.1*10−6 and 106.8*10−6 mg/kg/day, respectively. Although the estimated ADIs were below the current chronic reference dose (cRfD) of imidacloprid, we have stipulated the possible future downward revision of cRfD. The potential health risk of neonics to children via dietary exposure should raise more public concern considering the increase use of neonics and the ubiquitous presence in fruits and vegetables. Highlights • We aimed to assess the dietary risk of total neonicotinoids through fruit and vegetable consumption in school-aged children. • We used the relative potency factor approach to integrate all neonicotinoid residues in each food sample into a single metric. • The cumulative dietary risk of neonicotinoids through fruit and vegetable consumption was evaluated using the average daily intakes. • The estimated average daily intakes were not exceeded the chronic reference dose for imidacloprid, regardless the ubiquity of neonicotinoids in fruits and vegetables. • We have stipulated the possible future downward revision of the chronic reference dose for neonicotinoids for protecting public health. [ABSTRACT FROM AUTHOR]

Neonicotinoids (neonics), a class of systemic insecticides, have been frequently detected in pollen, vegetables, and fruits. Recently, an increasing concern has been aroused for human exposure to neonics. However, biological monitoring for quantifying body burden of neonics has rarely been reported. In this study, we developed an isotope-dilution ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method to simultaneously quantify nine neonics, including acetamiprid (ACE), thiamethoxam (THIAM), imidacloprid (IMIP), clothianidin (CLO), flonicamid (FLO), thiacloprid (THIAC), dinotefuran (DIN), nitenpyram (NIT), and imidaclothiz (IMIT) in urine. The limits of quantification were 0.1 μg/L for ACE, FLO, DIN, NIT and IMIT, and 0.2 μg/L for THIAM, IMIP, CLO, and THIAC. The overall recoveries were 80.8–103%, 81.5–91.7% and 83.0–92.3% for QA/QC samples fortifying at 1, 25, and 100 μg/L levels, respectively. UPLC/MS/MS method was used to analyze urine samples obtained from 10 children in Hangzhou, China. The detection frequencies were 80% for ACE and IMIP, 70% for THIAM and CLO, 20% for DIN and IMIT and 10% for THIAC. FLO and NIT were not detected in those urine samples. The data provided here will be helpful for conducting biological monitoring of neonics exposure in the future. [ABSTRACT FROM AUTHOR]

Neonicotinoids (Neonics) have become the most widely used insecticides around the world in recent years. Due to the hydrophilic character, neonics are emerging contaminants in drinking water. In this study, we aimed to characterize and quantify the fate and transport of neonics in the drinking water treatment system and their contributions to the overall dietary risks. Seven neonics in 97 surface and drinking water samples in the city of Hangzhou, China were analyzed. The relative potency factor method was adopted in order to calculate the total neonics concentrations. We then used the Monte Carlo simulation to calculate the chronic daily intake (CDI) of total neonics from water consumption. All 16 surface water samples collected from two rivers contained at least two neonics, and more than 93% of those contained 3 or more neonics. Imidacloprid was detected in all 16 surface water samples, followed by clothianidin and acetamiprid with average concentrations of 11.9, 7.6, 17.6 ng L-1, respectively. The drinking water treatment plants removed approximately 50% of neonics from surface water. However, 68 out of 71 tap water samples that we collected from the household faucets contained at least one neonic, with the highest average concentrations of 5.8 ng L-1 for acetamiprid. The maximum of CDIs of total neonics from water consumption for adult and children were 10.2 and 12.4 ng kg-1 d-1, respectively, which are significantly lower than the acceptable daily intake (ADI). The results presented here shown drinking water consumption only represented an insignificant portion of dietary risks of total neonics, mainly due to the modern drinking water treatment technologies that are capable of removing significant amount of neonics from drinking water. However, the ubiquity of neonics in the drinking water sources to kitchen faucets, should be a concern for public health. Image 1 • Fate and transport of neonicotinoids in the drinking water treatment system. • The ubiquity of neonics in drinking water. • The effectiveness of removing neonics from drinking water treatment plants. • Neonics in drinking water do not contribute significantly to the overall dietary risks. [ABSTRACT FROM AUTHOR]

Abstract Chlorophenols (CPs) have mainly been used as a biocide, wood treatment agent and a byproduct of bleaching in paper mills. They have been a topic of concern due to their wide spread and potential effects on human and wildlife. However, data on the thresholds and effects of the number of chlorine atoms on the endocrine-disrupting potential of CPs remain scarce. In this study, we adopted two in vitro models (reporter gene assays and H295R cell line) to investigate the endocrine-disrupting effects of four CPs (pentachlorophenol (PCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,4-dichlorophenol (2,4-DCP) and 2-chlorophenol (2-CP)). The molecular docking platform was adopted to further confirm the results of the in vitro assessment. Our results revealed that PCP exhibited oestrogen receptor alpha (ERα) agonistic activity at the concentration of 10−5 M and the value of REC 20 was 1.9 × 10−6 M. PCP and 2, 4, 6-TCP showed anti-oestrogenic activities with a RIC 20 value of 2.8 × 10−7and 2.9 × 10−6 M, respectively. Notably, only PCP exhibited thyroid hormone receptor beta (TRβ) antagonistic activity occurred at the concentration of 10−5 M, with a RIC 20 value of 1.3 × 10−6 M. The oestrogenic and thyroid hormone effects of CPs may be dependent on the number of chlorine atoms. A higher number of chlorine atoms indicated the higher effect of four CPs. The results of molecular docking were consistent with the reporter gene assay. For H295R cell line assay, PCP induced the StAR upregulation, while CYP17 was downregulated in a concentration-dependent manner by PCP and 2, 4, 6-TCP. Graphical abstract Image 1 Highlights • The thresholds of four CPs on the endocrine-disrupting potential were determined. • PCP exerted potential estrogenic and thyroid hormone activity. • CYP17 was downregulated in a concentration-dependent manner by PCP and 2,4,6-TCP. [ABSTRACT FROM AUTHOR]

Abstract The residues and risks of heavy metals in the environment and organisms have attracted great concern for many years. However, the information on their long-term spatiotemporal trends and potential health and ecological risks are scarce. In this study, a total of 1815 seawater samples, 451 sediment samples, and 54 seafood samples were collected in Xiangshan Bay, China, between 2011 and 2016. The residue, distribution, seasonal variation, and potential health risks of seven heavy metals in seawater, sediment, and seafood were evaluated. Dissolved Zn (mean = 16.8 μg L−1) and Cu (mean = 3.4 μg L−1) concentrations were high in seawater. Sediments were mainly contaminated by Zn (mean = 120.8 mg kg−1) and Cr (mean = 81.7 mg kg−1). The highest levels of Cu and Zn were observed in Ostreidae with the concentrations of 84.3 and 99.0 mg kg−1, respectively. The Kendall test indicated that only As, Cu, Cd, and Hg showed decreasing trends in seawater with time and no significant temporal trends were identified for heavy metals in sediment between 2011 and 2016. Only As may pose non-carcinogenic risks to both adults and children in some seafood. These data provide a reliable reference for government to use in developing reasonable and scientific regulations on the ecological and food safety of this area. Highlights • Long-term spatiotemporal trends of seven heavy metals were in seawater, sediment, and seafood were investigated. • The potential health risks in the seafood of this area were evaluated by hazard indexes. • As may pose non-carcinogenic risks to adults and children in some seafood in certain sites. [ABSTRACT FROM AUTHOR]