Endocrine Disruptors in our Oceans
The Institute for the Ocean and Fisheries at UBC in British Columbia made a concerning discovery regarding toxic chemicals present in the bodies of endangered Orca Whales off the coast of British Columbia between 2006 and 2018. These toxic chemicals were found to be associated with the paper and toilet paper industry. Surprisingly, the pollutants from the toilet paper industry accounted for a significant 46% of all identified pollutants.
One of the most prevalent toxic chemicals found was 4-nonylphenol (4NP), which is commonly used in pulp and paper processing, as well as in soap, detergent, and textile processing (3). In Canada, 4NP is recognized as a harmful substance that can negatively interact with the nervous system and impact cognitive function. Moreover, 4NP falls under the category of 'Forever chemicals,' known for their long-lasting environmental persistence. Forever chemicals belong to a group of Persistent Organic Pollutants (POPs) that are widely used in food packaging materials, stain and water-resistant fabrics, cookware, and fire extinguishers. The revelation of these findings has raised concerns about whether POPs are contributing to the decline in the number of orca whales (2).
This article sheds light on the potential risks not only to whale health but also to humans and other organisms exposed to POPs, particularly 4NP. The compound is a known endocrine disruptor and has a negative impact on the immune system (5). Furthermore, 4NP has been observed to cause damage to the male reproductive tract, being toxic to prostate epithelial cells and affecting spermiogenesis, which may contribute to the rise of prostate cancer and decreased male reproductive function (1). Studies involving pregnant rats exposed to high doses of 4NP (100 and 500mg/kg) have shown that they gave birth to male baby rats with stunted growth and weakened immune systems, an effect not observed in female babies.
The implications of these findings warrant caution regarding plastic additives introduced into our environment and food supply, including phthalates, bisphenols, and nonylphenols. All of these are endocrine disruptors that accumulate in the seafood supply and may eventually affect our health as well (4).
References:
1. Jeong, S.-H., Jang, J.-H., & Lee, Y.-B. (2022). Development of physiologically-based toxicokinetic-toxicodynamic (PBTK-TD) model for 4-nonylphenol (4-NP) reflecting physiological changes according to age in males: Application as a new risk assessment tool with a focus on toxicodynamics. Environmental Pollution, 312.
2. Kiah Lee, Juan José Alava, Paul Cottrell, Lauren Cottrell, Richard Grace, Ivona Zysk, Stephen Raverty. Emerging Contaminants and New POPs (PFAS and HBCDD) in Endangered Southern Resident and Bigg’s (Transient) Killer Whales (Orcinus orca): In Utero Maternal Transfer and Pollution Management Implications. Environmental Science & Technology, 2022; 57 (1): 360 https://www.sciencedaily.com/releases/2023/01/230112134725.htm
3. Limmun, W., Ishikawa, N., Momotori, J., Terasaki, M., Sato, T., Kikuchi, K., Sasamoto, M., Umita, T., & Ito, A. (2021). Degradation of the endocrine-disrupting 4-nonylphenol by ferrate(VI): biodegradability and toxicity evaluation. Environmental Science and Pollution Research, 1–9
4. Vered, G., & Shenkar, N. (2022). Limited effects of environmentally-relevant concentrations in seawater of dibutyl phthalate, dimethyl phthalate, bisphenol A, and 4-nonylphenol on the reproductive products of coral-reef organisms. Environmental Pollution, 314.
5. Xiang, R., Yan, J., Cheng, S., Yang, Y., Wang, H., Xie, J., Zhang, L., & Chen, J. (2022). Developmental immunotoxicity and its potential gender differences of perinatal exposure to 4-nonylphenol on offspring rats: JAK-STAT signaling pathway involved. Ecotoxicology and Environmental Safety, 237
