Comparative health risk assessment of BTEX exposures from landfills, composting units, and leachate treatment plants
This study assessed and compared the carcinogenic risks and hazard ratios of exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) within different units of a municipal solid waste disposal facility (Tehran, Iran), including the leachate treatment plant (LTP), the landfill, and a composting unit. Eight stations within the landfill site were sampled during summer and winter using NIOSH method 1501. The health risk assessment was conducted using the probabilistic risk model Oracle Crystal Ball. The probability distributions of risks were estimated. The average concentrations (±SD) of benzene, toluene, ethylbenzene, xylene, and total BTEX were 9.01 (± 5.22), 11.44 (± 6.62), 14.56 (± 9.8), 24.06 (± 14.86), and 59.09 (± 32.38) ppbv, respectively. BTEX concentrations were significantly higher downwind of the disposal site compared to those in the upwind direction. The maximum carcinogenic risks of benzene in LTP, landfill, and composting unit were in excess of 1 × 10−4. Hazard ratios of BTEX were sufficiently low so as not to pose a significant risk to the workers’ health. However, maximum hazard ratios of benzene and total BTEX within landfill exceeded 1. In general, lifetime cancer risks and hazard ratios of BTEX were higher in landfill area compared to leachate treatment plant or the composting unit. Sensitivity analyses indicated that concentration and exposure duration had the largest impacts on the variance of the estimated risks. Individuals working in the landfill were at higher risk. An action plan is needed to reduce the risks from BTEX exposure in waste facilities by reducing the concentrations and/or exposure duration.
KeywordsBenzene Cancer Occupational health VOCs Municipal solid waste Lifetime cancer risk
This study was funded by grant No. 25194 from Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences.
Compliance with ethical standards
Conflict of interest
The authors indicate that there are no conflicts of interest.
- Alahabadi A, Ehrampoush MH, Miri M, Ebrahimi Aval H, Yousefzadeh S, Ghaffari HR, Ahmadi E, Talebi P, Abaszadeh Fathabadi Z, Babai F, Nikoonahad A, Sharafi K, Hosseini-Bandegharaei A (2017) A comparative study on capability of different tree species in accumulating heavy metals from soil and ambient air. Chemosphere 172:459–467CrossRefGoogle Scholar
- Asante-Duah K (1993) Hazardous waste risk assessment. CRC PressGoogle Scholar
- Eller PM, Cassinelli ME (1994) NIOSH manual of analytical methods vol 94. Diane PublishingGoogle Scholar
- Hadei M, Hopke PK, Rafiee M, Rastkari N, Yarahmadi M, Kermani M, Shahsavani A (2018a) Indoor and outdoor concentrations of BTEX and formaldehyde in Tehran, Iran: effects of building characteristics and health risk assessment. Environ Sci Pollut Res 25:27423–27437. https://doi.org/10.1007/s11356-018-2794-4 CrossRefGoogle Scholar
- Hamid HHA, Jumah NS, Latif MT, Kannan N (2017) BTEXs in indoor and outdoor air samples: source apportionment and health risk assessment of benzene. J Environ Sci 1:49–56Google Scholar
- IRIS (1988) Chemical assessment summary: ethylbenzene; CASRN 100-41-4. U.S. Environmental Protection Agency: National Center for Environmental AssessmentGoogle Scholar
- IRIS (2003a) Chemical assessment summary: benzene; CASRN 71-43-2. U.S. Environmental Protection Agency: National Center for Environmental AssessmentGoogle Scholar
- IRIS (2003b) Chemical assessment summary: xylenes; CASRN 1330-20-7. U.S. Environmental Protection Agency: National Center for Environmental AssessmentGoogle Scholar
- IRIS (2005) Chemical assessment summary: toluene; CASRN 108-88-3. U.S. Environmental Protection Agency: National Center for Environmental AssessmentGoogle Scholar
- LaGrega MD, Buckingham PL, Evans JC (2010) Hazardous waste management. Waveland PressGoogle Scholar
- Nadal M, Inza I, Schuhmacher M, Figueras MJ, Domingo JL (2009) Health risks of the occupational exposure to microbiological and chemical pollutants in a municipal waste organic fraction treatment plant. Int J Hyg Environ Health 212:661–669. https://doi.org/10.1016/j.ijheh.2009.06.002 CrossRefGoogle Scholar
- US EPA (1986) Guidelines for carcinogen risk assessment: U.S. Federal Register, vol. 51, no. 185 (9/24/86) vol 51. Washington, DCGoogle Scholar
- US EPA (1989) Risk assessment guidance for superfund. Volume I: human health evaluation manual (part A) vol EPA/540/1-89/002. United StatesGoogle Scholar
- US EPA (1990) Clean Air Act; for hazardous air pollutants (HAPs). EPA United StatesGoogle Scholar
- US EPA (1999) Integrated risk information system (IRIS). EPA. Available at: https://www.epa.gov/iris
- US EPA (2005) Guidelines for carcinogen risk assessment. Risk Assessment Forum, US Environmental Protection Agency, United StatesGoogle Scholar
- World Health Organization (2010) WHO guidelines for indoor air quality: selected pollutants. WHOGoogle Scholar