We wish to share the scientific article entitled “Passive sampling of contaminants of emerging concern in a Caribbean urban estuary in Puerto Rico,” published in the peer-reviewed journal Marine Pollution Bulletin 213 (2025). The researchers of the study are Dr. Carlos J. Rodríguez Sierra and Dr. Imar Mansilla Rivera, professors in the Department of Environmental Health, School of Public Health, Medical Sciences Campus, and Dr. Jorge F. Bauzá-Ortega, scientific director of the Estuary.
By way of introduction, emerging contaminants of concern (ECCs) are a broad group of chemicals that includes pharmaceuticals such as antibiotics, antidepressants, and pain relievers, as well as personal care and hygiene products (PPCPs). ECCs also include illicit drugs (e.g., psychostimulants); artificial sweeteners (e.g., sucralose); material additives (e.g., surfactants, flame retardants, plastic ingredients); natural and synthetic hormones (e.g., estradiol, ethinylestradiol); and pesticides (e.g., atrazine). They also include degradation products of these substances, such as benzoylecgonine, a metabolite of cocaine.
As a result of this study, a total of 64 chemical precursors were detected in the San Juan Bay Estuary. Of these, 51 belonged to the group of active pharmaceutical ingredients (APIs), 12 were hormones, and one was sucralose. The 13 groups of chemical substances that achieved a 100% detection rate were mostly pharmaceuticals and are as follows: antidepressants (fluoxetine, amitriptyline, and sertraline); an antihistamine (diphenhydramine); an anticonvulsant (carbamazepine); an antifungal (miconazole); an anthelmintic (thiabendazole); a bronchodilator (theophylline); a fibrate (gemfibrozil); an illicit stimulant (cocaine); non-opioid analgesics (acetaminophen, ibuprofen, and naproxen); a stimulant (caffeine); and an insect repellent (N,N-diethyltoluamide – “DEET”). a plastic ingredient (bisphenol A); and an artificial sweetener (sucralose).
According to scientific literature, the detection of this mixture of 64 CPEs represents a potential risk to the estuary ecosystem. These risks include reproductive and developmental disorders, effects on the nervous system, endocrine disruption, and cancer. Furthermore, some CPEs can bioaccumulate in edible aquatic animals (e.g., fish), posing a risk to human health and the health of other predatory organisms such as the brown pelican.
Of particular concern is the presence in the estuarine system of endocrine disruptors (chemical substances capable of altering the hormonal system) such as the hormones detected in this study (androstenedione, estrone (E1), 17β-estradiol (E2), and 17α-estradiol). These estrogenic hormones have an adverse effect on the growth, development, and reproduction of aquatic species.
On the other hand, the presence of sucralose, a common indicator of water body contamination by untreated sewage discharges, suggests that these are the source of entry of these CPEs into the San Juan Bay Estuary.
Given the potential risks these pollutants pose to the health of the community and the estuarine ecosystem, the study's researchers recommend, among other things, eliminating untreated (illegal) sewage discharges into water bodies and optimizing the sanitary sewer system infrastructure. Furthermore, improved wastewater treatment technologies should be implemented to be more efficient at removing CPEs.
