Polycyclic aromatic hydrocarbons and organochlorine pesticides in rice hull from a typical e-waste recycling area in southeast China: temporal trend, source, and exposure assessment

Abstract

The residue levels of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) and 16 selected organochlorine pesticides (OCPs) in rice and rice hull collected from a typical e-waste recycling area in southeast China were investigated from 2005 to 2007. PAHs and OCPs also were measured in ten mollusk species (soft tissues) collected in an adjacent bay in 2007. Individual PAHs were frequently found in the entire sample set (including the rice, hull, and mollusk samples) with a detection rate of 73 %. The total concentrations of 16 PAHs (RPAHs) and 16 OCPs (ROCPs) were in the range of 40.8-432 ng/g dry weight (mean: 171 ng/g) and 2.35-925 ng/g (122 ng/g), respectively, which were comparable or higher than those reported in some polluted areas. Statistical comparisons suggested that the concentrations of contaminants in hull gradually decreased from 2005 to 2007 and the residue levels were generally in the order of mollusk, hull, and rice, on a dry weight basis. Principal component analysis in combination with diagnostic ratios implied that combustion of coal, wood, and plastic wastes that are closely associated with crude e-waste recycling activities is the main source of PAHs. The finding of decreasing trend of concentrations of PAHs in this area is consistent with the efforts of local authorities to strengthen regulations on illegal e-waste recycling activities. Composition analysis suggested that there is a recent usage or discharge of hexachlorocyclohexane and dichlorodiphenyltrichloroethane into the tested area. The estimated daily intake (EDI) of RPAHs and ROCPs (calculated from mean concentrations) through rice and mollusk consumption was 0.411 and 0.921 lg/kg body weight (bw)/day, respectively.

Male and female mice show significant differences in hepatic transcriptomic response to 2,3,7,8-tetrachlorodibenzo-p-dioxin

“…Chlorinated dioxins are a large class of environmental contaminants generated as by-products of a variety of industrial processes [ 1 ]. Dioxin exposure can lead to a variety of toxic outcomes, and concerns surrounding widespread human exposure have led many of these to be extensively studied in model organisms [ 2 – 6 ]. To date, most studies of dioxin-induced toxicity have focused on the most potent and toxic congener, 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD).…”

“…To date, most studies of dioxin-induced toxicity have focused on the most potent and toxic congener, 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD). At high doses, TCDD has been associated with numerous toxic outcomes in humans, including severe chloracne, neurotoxicity and tumourigenesis [ 3 , 6 – 8 ]. In animal models, even small doses of TCDD have been shown to cause a wide range of toxicities, the severity and duration of which differ among species [ 2 , 9 , 10 ].…”

Pollution profiles and risk assessment of PBDEs and phenolic brominated flame retardants in water environments within a typical electronic waste dismantling region

“…(Wong et al 2007;Zhang et al 2011). In addition to heavy metals of concern, various hazardous organic compounds are released into the environment during these dismantling processes Liu et al 2014). Brominated flame retardants (BFRs), used to reduce the flammability of electrical and electronic products and textiles, are among the organics which are recently receiving the most attention.…”

Overview of chemical hazards in cereals, seeds and nuts

“…High concentrations of PAHs were found in rice and rice hulls (40.8-138 ng/g and 67.7-412 ng/g, respectively) in a region in China, grown on highly contaminated soil in rice paddies in areas close to electronic waste recycling activities (combustion of plastic waste, wood and coal). Higher concentrations were found in the hulls than in the rice, which may be explained by the fact that the outside layers of the rice are more exposed to the PAHs released from the recycling activities (Liu et al, 2014). Chen et al…”