Environmental impact of effluent discharge from a fishing company on marine water quality: a case study in a coastal area of ​​northern Peru

Abstract

This study assessed the influence of industrial effluents from a fishmeal processing company (consumo humano indirecto, CHI) on the environmental quality of Puerto Malabrigo Bay (La Libertad, Peru). A non-experimental, descriptive-correlational design was applied, analyzing environmental monitoring records from 2024–2025 during production and closed seasons. Results showed that although most parameters regulated by the Marine Coastal Water Quality Standards (ECA, 2017) and the Fishery Effluent Standards (LMP, 2018) were met, production periods exhibited increased BOD₅, reduced dissolved oxygen, and peaks of thermotolerant coliforms, evidencing localized environmental deterioration. The high organic and microbiological load of the effluent, despite not being regulated, was critical in explaining the alterations observed in the receiving body. These findings confirm that partial regulatory compliance does not ensure effective protection of marine ecosystems and highlight the need to update regulations, optimize effluent treatment systems, and implement more comprehensive monitoring programs. It is concluded that environmental management in the fishery industry must go beyond formal compliance, incorporating critical parameters currently not considered and adopting preventive and adaptive approaches to ensure the sustainability of marine-coastal ecosystems.