# Integrated water quality assessment and health risk analysis of heavy metal and microbial contamination in the Ichu River, Peru

## TL;DR

This study assesses water quality and health risks in the Ichu River in Peru, finding severe contamination from heavy metals and microbes, urging immediate action to protect public health and the environment.

## Contribution

The study integrates water quality assessment with health risk analysis, identifying key pollution sources and their impacts in the Ichu River.

## Key findings

- Water quality deteriorates downstream with increased turbidity, TDS, conductivity, and BOD.
- Heavy metals (As, Pb, Cd, Cr) and E. coli contamination exceed WHO standards due to mining and industrial discharge.
- Principal Component Analysis links heavy metals, microbial pollution, and organic load as main causes of water degradation.

## Abstract

The Ichu River serves as the primary water source for urban and agricultural use and industrial operations, but anthropogenic pollution has a serious negative impact on its water quality.

The investigation measured water quality and health-related risks by analyzing physicochemical parameters, heavy metals, and microbial pollutants at eight sampling points, site 1 (S1) through (S8).

The research data showed that water quality worsened progressively from upstream to downstream locations such as turbidity, TDS, conductivity, and BOD levels increased. Oil pollution and oxygen depletion arose from a reduction in dissolved oxygen from 6.3 to 4.5 mg/L at the different sampling sites (S1 to S8). Heavy metals (As, Pb, Cd, and Cr) in the samples exceeded the standards established by the World Health Organization (WHO) established standards because of mining and industrial wastewater and local wastewater discharge. The presence of excessive
Escherichia coli (E. coli) and total coliforms in microbial tests proved that the water was severely contaminated by fecal matter. Principal Component Analysis showed that heavy metals exist with microbial pollution and organic load as the main sources of water quality decline, and pollution indicators were found to establish powerful relationships with depleted oxygen levels.

The severe contamination risks found in this study justify immediate pollution control measures, wastewater treatment enforcement, and sustainable watershed management practices. Urgent action is necessary because vital parameters surpass the standards set by the WHO and (United States Environmental Protection Agency (USEPA) to avoid enduring environmental damage and health problems. This research demonstrates the value of continuing water quality assessments while enforcing policies and raising public awareness to improve the water quality of the Ichu River.