In a groundbreaking environmental study conducted by Simon Fraser University researchers, alarming levels of fiberglass contamination have been discovered in the Cowichan Estuary, situated on Vancouver Island. This estuary, covering approximately 400 hectares, represents one of the largest intertidal ecosystems in British Columbia and holds immense ecological and cultural significance. It serves as a vital habitat for migratory shorebirds and supports the livelihoods and food security of the Cowichan Tribes First Nations, who have entrusted this area for generations. The research marks a critical step in exposing the presence of a previously overlooked pollutant—fiberglass particles—that threatens aquatic life, birds, and communities dependent on seafood.
Fiberglass, a silica-based composite material often reinforced with plastic resins, is widely used in marine industries for boat hulls and various coastal infrastructures. However, its persistence in the environment and potential toxicological effects remain poorly understood. The newly released study reveals that fiberglass particles are not only pervasive but are becoming increasingly prevalent in estuarine sediments and biofilms. Researchers analyzed sediment and biofilm samples from 26 different sites across the Cowichan Estuary over a span of four years, spanning from 2020 to 2024. They detected fiberglass particles at an astounding 96% of sediment locations—a significant increase from just 64% in the initial 2020 survey—highlighting an escalating contamination trend.
The sediment samples, especially those collected near areas with intense industrial operations and log transportation channels, exhibited the highest concentrations of fiberglass particles. Quantifications ranged from six up to 286 particles per kilogram of dry sediment, with industrial and marine infrastructure zones emerging as hotspots. Simultaneously, the study identified substantial fiberglass contamination in the biofilm layers—comprising the vital top three to five millimeters of microbial and algal assemblages that form the primary food source for migratory shorebirds. Sites adjacent to mill ponds, cargo terminals, and bustling marinas showed biofilm pollution ranging between 30 and 62 particles per kilogram of dry weight.
This data implicates multiple sources contributing to this pervasive problem. Industrial facilities such as wood processing mills and port terminals discharge fiberglass-laden runoff through stormwater and other uncontrolled channels. Meanwhile, everyday marine activities—like boat maintenance, hull sanding, and repairs at slipways and boatyards—generate fiberglass dust and debris that easily enter adjacent water bodies. Notably, derelict and abandoned boats, subjected to ongoing weathering and decay, represent a persistent and unregulated source of microfiberglass pollution, analogous to microplastics widely recognized today. The fragmentation process converts fiberglass-reinforced plastic materials into microscopic, needle-like particles that accumulate in sediments and aquatic food webs.
Fiberglass’s physical and chemical characteristics underscore the urgency for attention. Being denser than seawater, fiberglass particles tend to settle and embed deeply within the intertidal sediment strata where benthic invertebrates—clams, mussels, and other shellfish—reside and feed. The biofilms also trap these particles in their thin, nutrient-rich matrices, providing a direct vector for particle ingestion by migratory birds and aquatic fauna. Despite the alarming presence of fiberglass in these ecological compartments, the toxicological thresholds for harm remain largely unknown. The extent to which organisms can excrete or biologically accumulate fiberglass fibers, and potential cascading impacts through the food web, are open questions that must be urgently addressed.
Juan José Alava, the study’s lead marine eco-toxicologist, emphasized the critical knowledge gap and consequences of inaction: “We are still in the infancy of understanding how fiberglass contaminates estuarine ecosystems and what this means for wildlife and human health. The presence of these particles in a crucial Indigenous food source alone demands immediate and precautionary interventions, even before all toxicological details are resolved.” The findings challenge policymakers and industry stakeholders to reassess management frameworks and incorporate this emerging contaminant into regulatory agendas.
The study’s publication in Marine Pollution Bulletin represents one of the first baseline assessments of coastal fiberglass pollution in Canada. It sets a precedent for rigorous environmental monitoring of synthetic composite pollutants, highlighting how human industrial and maritime activities introduce novel contaminants into fragile estuarine ecosystems. Given the estuary’s designations as an Important Bird Area and a food harvesting site for First Nations, these findings resonate beyond academic circles, underscoring broader ecological justice and community well-being concerns.
To mitigate the growing fiberglass contamination threat, the research recommends multiple feasible interventions aligned with sustainable marine and coastal stewardship. Stricter controls and improved best management practices at slipways and boatyards are necessary to capture and reduce fiberglass debris generated during sanding, cutting, and hull maintenance. Enhanced regulatory oversight and infrastructure improvements in industrial runoff and stormwater management could substantially decrease the influx of fiberglass particles into the estuary. Furthermore, policies advocating for responsible end-of-life boat disposal, including recycling and safe dismantling programs for fiberglass hulls, are urgently needed.
Advances in material science and green chemistry offer hopeful avenues for reducing long-term environmental impacts. Developing and adopting alternative marine materials with lower fragility and enhanced degradability could transform industrial practices and mitigate contamination risks moving forward. Such innovation requires multi-sector collaboration that bridges scientific research, industrial design, government regulation, and community engagement to safeguard marine ecosystems and the human populations reliant upon them.
Ultimately, the discovery of microfiberglass pollution in the Cowichan Estuary serves as a cautionary tale about the unintended consequences of technological progress without adequate environmental foresight. The study’s compelling evidence calls for immediate preventive action rather than reactive remediation, as fiberglass contamination poses a stealthy but growing challenge to estuarine health, biodiversity, and Indigenous food sovereignty. Prioritizing research expansion into fiberglass toxicity, environmental transport, and ecological interactions will be crucial in forming cohesive policies geared toward sustainable marine ecosystem management across Canada’s west coast and beyond.
The Cowichan Estuary investigation marks a pivotal step forward in environmental science and coastal conservation, shedding light on a dangerous yet under-recognized pollutant. As more estuaries worldwide face similar pressures from industrialization and maritime traffic, this study highlights how vigilance, interdisciplinary research, and preventive governance can help stem emerging threats to our global inland waters and coastal communities.
Subject of Research: Fiberglass particle contamination in estuarine sediments and biofilms and its ecological implications.
Article Title: Assessing fiberglass particles in intertidal biofilm and sediments at an anthropogenically impacted estuary in Canada’s west coast
News Publication Date: 2-Jan-2026
Web References:
https://www.sciencedirect.com/science/article/pii/S0025326X25016637
Image Credits: Photo courtesy of the Cowichan Estuary Restoration and Conservation Association (CERCA).
Keywords: Fiberglass pollution, estuary contamination, marine eco-toxicology, Cowichan Estuary, Vancouver Island, sediment biofilm, microfiberglass, marine environmental health, Indigenous food security, industrial runoff, marine infrastructure pollution, sustainable coastal management
