Mobilization of per- and poly-fluoroalkyl substances (PFAS) in soils with different organic matter contents.

There is considerable interest in addressing soils contaminated with per- and polyfluoroalkyl substances (PFAS) because of the PFAS in the environment and associated health risks. The neutralization of PFAS in situ is challenging. Consequently, mobilizing the PFAS from the contaminated soils into an aqueous solution for subsequent handling has been pursued. Nonetheless, the efficiency of mobilization methods for removing PFAS can vary depending on site-specific factors, including the types and concentrations of PFAS compounds, soil characteristics. In the present study, the removal of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) from artificially contaminated soils was investigated in a 2D laboratory setup using electrokinetic (EK) remediation and hydraulic flushing by applying a hydraulic gradient (HG) for a duration of 15 days. The percent removal of PFOA by EK was consistent (∼80%) after a 15-day treatment for all soils. The removal efficiency of PFOS by EK significantly varied with the OM content, where the PFOS removal increased from 14% at 5% OM to 60% at 50% OM. With HG, the percent removal increased for both PFOA and PFOS from about 20% at 5% OM up to 80% at 75% OM. Based on the results, the mobilization of PFAS from organic soil would be appropriate using both hydraulic flushing and EK considering their applicability and advantages over each other for site-specific factors and requirements.

Occupational Health Hazard Exposure among municipal solid waste workers in Himachal Pradesh, India.

The net volume of Municipal Solid Waste (MSW) generated in Himachal Pradesh is 350 tons per day (TPD) with an annual growth rate varying between 1 and 1.33%. This leads to serious considerations regarding potential occupational health hazards of workers associated with MSW. The study generated from non-engineered landfill sites was carried out at three locations- Shimla, Solan, and Mandi in Himachal Pradesh, India. . The main aim of this study was to determine existing occupational hazards in relation to MSW management at these locations, to coordinate with the different municipalities and suggest suitable remedial measures for our study locations. In particular, the exposure assessment to the work force comprising of street sweeping, waste collection, waste processing, and rag picking were assessed using an interview scheduling technique. A questionnaire survey was carried out on these workers with the questions asked related to their work culture, socio-economic conditions, general awareness of occupational health risks and related occupational health hazards associated with the work being performed by them. The results showed that the workforce mainly comprised of males with a low percentage of literacy rates. The age distribution showed that majority of waste collectors and street sweepers were above 30 years of age (67%) and that the rag pickers in Mandi town were below 20 years of age. Income variation between casual and regular workers was highly significant with regular workers (INR 600-1200; USD 9-18) getting almost six times the payment of the casual workers (INR 100-200; USD 3-7.5). From the studies conducted the study deduced that about 64% of waste collectors, 80% of street sweepers and 10% of rag pickers in Solan and about 6.67% street sweepers, 57.47% waste collectors and 100% of rag pickers in Mandi were not provided with any protective equipment. Interestingly, in the capital city of Shimla a small fraction of the street sweepers (28%) and waste collector (6%) confirmed that they were given protective equipment twice in a year. The lack of provisions of protective equipment along with the ignorance of the workers results in occupational health hazards due to different types of external injuries. The major occupational health issues reported by various categories of waste workers were muscle and ligament sprain, cuts and lacerations and different allergies varying between 1.97 and 66.67% [ for e.g. in Solan it varies from 32.47-66.67%; Shimla 1.97-10.16% and in Mandi 9.52-16.67%], 6.36-67.95% and 5.77-42.86%, respectively. From this study, it was observed that such workers are ill-protected against such occupational health hazards new laws and policies are needed to be introduced for their protection.