Rural village as a source of microplastic pollution in a riverine and marine ecosystem of the southern Venezuelan Caribbean

Microplastics (MP) are widely distributed environmental pollutants with the potential to impact terrestrial and aquatic ecosystems. MP produced in urban areas are transported through rivers to marine environments, interacting with water, sediments and organisms along the way. To date, most studies have characterized MP pollution associated with urban centers. This study quantified the MP abundance associated with a representative rural community of the Southern Caribbean Coast of Venezuela, Chichiriviche de la Costa (Chichi), and its influence on a neighboring riverine and marine ecosystem. MP pollution was assessed in the dry and rainy season by sampling riverine water and sediments upstream and downstream of the village. Additionally, marine water, sediments and organisms (fish and sponges) were sampled in the bay. Samples were processed according to standardized protocols with strict quality control procedures. MP were characterized through ATR-FT-IR. The riverine water and sediments downstream of the village had a MP abundance that was 2.3 and 3.8 times higher than the upstream sampling site, respectively. A higher MP abundance was found in the sediments of the river mouth and the waters of the inner bay of Chichi, suggesting that the river was the main source of MP to the bay. MP were found in all marine organisms. The MP abundance in the waters of the inner bay of Chichi was 1.7 to 1197.3 times higher than previous studies conducted in urban centers of Latin America. Our study highlights the role of rural centers as sources of MP pollution.