Using Polychlorinated Naphthalene Concentrations in the Soil from a Southeast China E-Waste Recycling Area in a Novel Screening-Level Multipathway Human Cancer Risk Assessment

Abstract

Polychlorinated naphthalene (PCN) concentrations in the soil at an e-waste recycling area in Guiyu, China, were measured and the associated human cancer risk due to e-waste-related exposures was investigated. We quantified PCNs in the agricultural soil and used these concentrations with predictive equations to calculate theoretical concentrations in outdoor air. We then calculated theoretical concentrations in indoor air using an attenuation factor and in the local diet using previously published models for contaminant uptake in plants and fruits. Potential human cancer risks of PCNs were assessed for multiple exposure pathways, including soil ingestion, inhalation, dermal contact, and dietary ingestion. Our calculations indicated that local residents had a high cancer risk from exposure to PCNs and that the diet was the primary pathway of PCN exposure, followed by dermal contact as the secondary pathway. We next repeated the risk assessment using concentrations for other carcinogenic contaminants reported in the literature at the same site. We found that polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) and PCNs caused the highest potential cancer risks to the residents, followed by polychlorinated biphenyls (PCBs). The relative importance of different exposure pathways depended on the physicochemical properties of specific chemicals.

Assessment of knowledge, attitude, perceptions and risk assessment among workers in e-waste recycling shops, Thailand

“…(2) Average daily dose (ADD) of airborne was determined using the equation below. ADD = CxInhRxEFxED/BWxATxPEF (3) Where C is the concentration of Pb and Cd in dust (mg/L), drinking water (mg/L), and personal air samples (data from laboratory analysis), IR is the ingestion rate (2 L/day for age over 6 years old, U.S. EPA 1989) [23], EF is the exposure frequency (360 days/year) [24], ED is the exposure duration (average of exposure duration of workers 13 years) [24], BW is the body weight (average of body weight of workers 62 kg, from questionnaires), AT is the average time of exposure (ED×365 days/year) , PEF is the particle emission factor in m 3 kg-1 [25]. When hazardous quotients (HQ) and hazard index (HI) values are less than one, there is no risk to the population, but if these values exceed one, there may be concern for potential noncarcinogenic effects [23].…”

“…Most of them are heavy metals such as lead, mercury, cadmium, chromium and beryllium, as well as other dangerous substances found in large quantities as well, brominated flame retardants, le vinyl chloride (polyvinyl chloride, PVC) polychlorinated biphenyl polychlorinated biphenyls, PCBs, triphenyl phosphate (TPP), nonylphenol (nonylphenol, NP), and polychlorinated naphthalene. Polychlorinated naphthalene, PCNs, dioxins and furans can contaminate the environment [ 3 ]. The health effects of chemical exposure from electronic waste include effects on the central nervous system and brain causing symptoms of irritability, anxiety, lethargy, dizziness, staggered walking, easy falling, insomnia, personality changes, and amnesia in severe cases.…”

Insights into the Formation and Profile of Chlorinated Polycyclic Aromatic Hydrocarbons during Chlorobenzene and Chloroethylene Manufacturing Processes

“…PCNs and Cl-PAHs are ubiquitous in multiple environmental matrices, including atmosphere, airborne particulate matter, soil, water, and sediments. − These compounds have been shown to be potentially immunotoxic and carcinogenic by binding to the aryl hydrocarbon receptor . Exposure to PCNs and Cl-PAHs occurs by inhalation, ingestion of contaminated food and water, and dermal contact. , These lipophilic compounds can accumulate and transfer through the food chain .…”

Improved Pesticide Product Labeling Information for Household Lawn Management: Recommended Safe Durations in Support of Minimizing Children’s Exposure to Pesticides

“…The half-lives of pesticides in the lawn environment were obtained from modeling studies in the literature (first-order kinetic screening models). ,, Because the household application method of pesticides typically differs from that of croplands (i.e., intensive aerial sprays), in this study, we assumed that, after pesticide application on lawns, pesticide residues would first deposit on the grass surface and in surface soil compartments and then be transported to the air. Thus, dissipation half-lives of pesticides on the grass surface and in surface soil compartments were used, and the residue level in the air was estimated based on a simple partitioning rule. , …”

“…Pesticide fate models have been extensively studied, ranging from screening-level models for the regulatory purpose to advanced models with high-spatial resolutions . Screening-level models simplify the simulation process by assuming homogeneous distributions of pesticides in environmental compartments (e.g., soil, air, and plants) and using generic values of model input variables for point estimation, which typically consider the worst scenario and are suitable for regulatory practice. , Advanced models consider the dynamic change of environmental conditions, providing probabilistic and spatiotemporal simulations, which rely on intensive computation but enable higher tier risk assessments to be conducted. − …”