Contaminants of emerging concern in surface waters in Barbados, West Indies

Abstract

Contaminants of emerging concern (CECs), including pharmaceuticals, artificial sweeteners, steroid hormones, and current-use pesticides have been detected in surface waters around the world, but to date, there have been no reports in the peer-reviewed literature on the levels of these classes of contaminants in freshwater resources in the Caribbean region. In the present study, multi-residue solid phase extraction (SPE) and liquid chromatography with tandem mass spectroscopy (LC-MS/MS) were used to analyze grab samples of surface waters collected from five different watersheds in Barbados, West Indies. The artificial sweeteners (AS), acesulfame, cyclamate, saccharin, and sucralose were widely detected in the watersheds, indicating contamination from domestic wastewater, and the concentrations of these chemical tracers in water were correlated with the concentrations of the non-prescription pharmaceutical, ibuprofen (R values of 0.4-0.6). Surprisingly, the concentrations of another chemical tracer of domestic wastewater, caffeine were not correlated with ibuprofen or AS concentrations. Several other prescription pharmaceuticals and the steroid hormones, estrone and androstenedione, were detected in selected watersheds at low ng/L concentrations. The fungicide, chlorothalonil was widely detected in surface waters at low (< 10 ng/L) concentrations, but the levels of this pesticide were not correlated with the concentrations of the other target analytes, indicating that the source of this pesticide is not domestic wastewater. An informal survey of disposal practices for out of date or unused drugs by pharmacies in Barbados indicated that disposal into trash destined for the landfill and flushing down the sink might be significant sources of contamination of water resources by pharmaceuticals.

Assessing Occurrence and Biological Consequences of Contaminants of Emerging Concern on Oceanic Islands

“…The antibiotic sulfamethoxazole was found in most samples, but usually at low ng/L concentrations. This is consistent with a study from Barbados [6] where this pharmaceutical was frequently detected below the level of quantitation. For two of three sampling events, the insect repellent DEET was present at concentrations approaching 500 ng/L at Waikaumalo Stream.…”

“…In Hawai'i, most existing data were collected in marine or estuarian environments surrounding the archipelago [4,5]. The potential impacts of these CEC on the freshwater biota of islands like Hawai'i are not well understood, as few studies have focused on these distinct environments (e.g., [6]).…”

Impact of Solute Properties and Water Matrix on Nanofiltration of Pesticides

“…Crop depletions from non‐use of pesticides would inevitably result in a rise in food prices. Nevertheless, sprayed pesticides can become one of the main contaminants in water sources or soil , and there is much evidence of the consequent bioaccumulation of pesticides in fish and of the presence of pesticides in dairy products . Human health is also at risk from the presence of pesticides in drinking water sources as most of the treatment processes are not targeted specifically for pesticide removal .…”

Photochemical degradation of aqueous artificial sweeteners by UV/H2O2 and their biodegradability studies

“…ACE was detected in all samples ranging between 19 ng/L to 571 ng/L. SUC was detected in three out of four, however in much smaller concentrations in the range of 3 ng/L to 19 ng/L (Edwards et al, 2017).…”