A Review of Health Risks and Pathways for Exposure to Wastewater Use in Agriculture

Abstract

Background:Wastewater is increasingly being used in the agricultural sector to cope with the depletion of freshwater resources as well as water stress linked to changing climate conditions. As wastewater irrigation expands, research focusing on the human health risks is critical because exposure to a range of contaminants must be weighed with the benefits to food security, nutrition and livelihoods.Objectives:The goal of this paper was to review research examining health risks and exposure pathways associated with wastewater irrigation to identify research trends and gaps.Methods:We conducted a review of the literature and identified a total of 126 studies published from 1995 to 2013. Findings were summarized based on several themes including types of exposure pathways, wastewater contaminants, methodological approaches and the geographical distribution of research.Results:Only 23 studies used epidemiological methods, while most research applied alternative methods to estimate risk, such as quantitative risk assessment models or comparisons of crop contamination to established guidelines for wastewater reuse. A geographic breakdown demonstrated a focus on microbiological contaminants in specific regions such as sub-Saharan Africa and Southeast Asia, despite growing chemical risks associated with rapid urbanization and industrialization that may change the types and distribution of wastewater contaminants.Conclusions:To provide a more comprehensive understanding of the health risks of wastewater use in agriculture, future research should consider multiple exposure routes, long-term health implications, and increase the range of contaminants studied, particularly in regions heavily dependent on wastewater irrigation.Citation:Dickin SK, Schuster-Wallace CJ, Qadir M, Pizzacalla K. 2016. A review of health risks and pathways for exposure to wastewater use in agriculture. Environ Health Perspect 124:900–909; http://dx.doi.org/10.1289/ehp.1509995

Rapid treatment of greywater (household sewage) by terrestrial weed Achyranthes aspera in SHEFROL® reactors

“…But that is done more out of compulsion than choice-due to the shortage of raw water prevailing now in most regions. But wastewater irrigation, unless done with greywater that has been treated to meet the standards for use in irrigation, can seriously contaminate the environment and pose health risks [8][9][10][11]. In a few studies, suits of several species of plants along with sand or soil as filter media have been used to reduce the pollutant load of greywater and enhance its utility for irrigation [12][13][14][15], but no study exists on the use of any specific terrestrial plant for greywater treatment [16,17].…”

Towards “Sustainable” Sanitation: Challenges and Opportunities in Urban Areas

“…For example, in Accra 280,000 residents were found to consume vegetables from urban farming irrigated with wastewater [24]. While urban agriculture constitutes an important element of food security in many cities, high pathogen and chemical content in untreated wastewater presents serious health risks for consumers of irrigated produce, urban farmers and their families [25].…”

The mutual influences of man-made pollutants and allergic manifestations

“…In addition, wastewater has been linked to viral, bacterial and protozoan diseases leading to e.g. salmonellosis, shigellosis, cholera and hepatitis A (Dickin, Schuster-Wallace et al, 2016). In the capital of Bangladesh, Dhaka, it was shown, however, that the use of improved water sources and sanitation had a significant positive impact on the incidence of childhood diarrhea (Kamal, Hasan et al, 2015).…”