Countries of the Wider Caribbean acknowledged over 30 years ago that untreated wastewater had damning effects on human and environmental health. Improving the quality of wastewater that entered our waterways therefore became a priority for countries; but dangerous chemicals hitchhiking in treated and untreated wastewater was a more distant thought. While projects like the Global Environment Facility-funded Caribbean Regional Fund for Wastewater Management (GEF CReW) have supported Caribbean countries in improving their wastewater management, the presence and detectability of chemical contaminants in treated wastewater are now a further cause for concern.
Contaminants of emerging concern (CECs) or emerging contaminants, as these chemicals or micro-pollutants are called, primarily include pharmaceuticals and personal care products (PPCPs) that are intentionally or unintentionally released into our environment. There is no in-depth understanding of the risks they may pose to humans, the environment, and aquatic life. However, they often come from household cleaning agents, paints, medicines including antibiotics given to animals, fragrances, pesticides, preservatives, toiletries, laundry detergents, cosmetics and a range of other domestic and industrial products that are released from factories, farms, wastewater treatment facilities, hospitals and our homes. The widespread use, diverse points of origin of these contaminants and their contact with other chemicals makes them difficult to study, bringing into question their effect on lifeforms.
Impacts on human and environmental health
The Caribbean relies heavily on marine and coastal resources for food, livelihoods and tourism; coincidentally these resources are also receptacles of our treated and untreated wastewater. Emerging contaminants have hitchhiked through sewers and wastewater treatment plant outfalls into our marine and coastal waters, and sometimes through leaching from landfills into ground water. As many countries rely on ground and surface waters for drinking, recreation and economic growth, there is a concern about chemically-contaminated effluent seeping into these waters. The thought process becomes- what harms the marine environment, harms food security, exports, ecotourism, livelihoods and perhaps human health.
The risks to human and environmental health continue to be investigated and are yet to be fully understood. In fact, the effects of emerging contaminants might not be readily visible or identifiable for years to come, over which time the damage may become extensive. There is some consensus on the potential for these contaminants to influence various cancers, developmental, reproductive and other defects and illnesses resulting from their toxicity and the endocrine disrupting properties they possess. Endocrine disruptors generally have adverse effects on the hormones in human and other lifeforms. While the concentrations of these micro-pollutants might be too low to determine human health impacts, it is suggested that they are high enough to potentially harm aquatic ecosystems. Negative effects detected through laboratory testing on fish and organisms suggest transmissible threats to human beings and lifeforms within the food chain. However, research into the correlation between exposure to emerging contaminants and human health must also take into consideration mixtures with other contaminants, and external and pre-existing conditions which have led scientists to more reserved conclusions on the short- and long-term effects. What is clear is that scientists and wastewater engineers must now devise financially-feasible methods and wastewater treatment infrastructure options capable of removing chemical matter from wastewater.
Investment in Wastewater Treatment – a Challenging Solution
The Global Environment Facility-funded Caribbean Regional Fund for Wastewater Management (GEF CReW) project, implemented from 2011-2017, tested financial mechanisms for investment in wastewater management. Across the project’s 13 participating countries, ways of sustainably financing wastewater management were found, capacity in wastewater management was enhanced, legislative and policy reforms were done, and wastewater treatment plants across four countries were upgraded, decommissioned and refurbished. Despite this, the challenge throughout the Region is that domestic and industrial sewage are generally discharged through the same sewers thereby increasing the chemical content in wastewater that enter our marine and coastal environments. Additionally, pretreatment of industrial chemicals before discharge to wastewater treatment plants is not heavily regulated nor is it standard practice across the region.
Furthermore, Wider Caribbean countries share a challenge of identifying sustained funding for improvements in the wastewater sector including the maintenance of wastewater treatment plants. Moreover, even at the tertiary level, conventional methods of wastewater treatment cannot accommodate the removal of some micro-pollutants. This becomes further compounded by the emerging need to design and upgrade wastewater treatment infrastructure to adequately address the fast-growing issue of chemicals in our wastewater and consequently our water bodies. Additionally, chemicals linger in wastewater sludge- which is sometimes used as fertilizer for crops, eventually seeping into water bodies, meaning that there is further processing required for chemical content to be removed from sludge before its application to soil.
The lack of scientific evidence and an understanding of the effects of emerging contaminants on humans, ecosystems, soil and our waters present a challenge for states to take political action. Nevertheless, taking an environmentally-responsible approach to wastewater disposal in light of the concern for emerging contaminants is gaining traction as a regional priority. The successes and lessons learnt from the GEF CReW’s testing of financial mechanisms avail an opportunity for countries to find innovative solutions for ensuring environmentally sound and cost-effective wastewater management. By encouraging investment in the wastewater sector, the Wider Caribbean can potentially join other parts of the world that are using advanced technology options for removing chemicals such as through the use of activated carbon; and identify an integrated approach for managing harmful chemicals in our wastewater and for securing funding in this regard.
The issue of emerging contaminants and their threat to human and environmental health brings into perspective the interrelationship between the choices we make in our daily lives and their impacts on our environment. Proper wastewater management is everyone’s responsibility and the conditions for an enabling environment for investment in wastewater management must be seen as a national and regional priority to promote a sustainable future for all.
A series of case studies from the GEF CReW project demonstrate the lessons learnt, challenges and successes in wastewater management across the region and guide us in creating the conditions conducive to sustainably managing our wastewater sector.
By Chrishane Williams
Global Environment Facility funded Caribbean Regional Fund for Wastewater Management (GEF CReW) Project
United Nations Environment Caribbean Environment Programme (CEP)
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