Metals exposures of residents living near the Akaki River in Addis Ababa, Ethiopia: a cross-sectional study.

Ellen Yard,Andualem Mekonnen,Danielle Rentz Hunt,Almaz Abebe,Matthew Murphy,Tsigereda Assefa,Kathleen L Caldwell,Tesfaye Bayleyegn,Kirubel Tesfaye,Lauren Lewis,Richard Luce,Firehiwot Abera,Feyissa Chala,Amha Kebede,Kifle Habte,Moa Abate

doi:10.1155/2015/935297

Abstract

Background. The Akaki River in Ethiopia has been found to contain elevated levels of several metals. Our objectives were to characterize metals exposures of residents living near the Akaki River and to assess metal levels in their drinking water. Methods. In 2011, we conducted a cross-sectional study of 101 households in Akaki-Kality subcity (near the Akaki River) and 50 households in Yeka subcity (distant to the Akaki River). One willing adult in each household provided urine, blood, and drinking water sample. Results. Urinary molybdenum (p < 0.001), tungsten (p < 0.001), lead (p < 0.001), uranium (p < 0.001), and mercury (p = 0.049) were higher in Akaki-Kality participants compared to Yeka participants. Participants in both subcities had low urinary iodine; 45% met the World Health Organization (WHO) classification for being at risk of moderate iodine deficiency. In Yeka, 47% of households exceeded the WHO aesthetic-based reference value for manganese; in Akaki-Kality, only 2% of households exceeded this value (p < 0.001). There was no correlation between metals levels in water samples and clinical specimens. Conclusions. Most of the exposures found during this investigation seem unlikely to cause acute health effects based on known toxic thresholds. However, toxicity data for many of these metals are very limited.

Highlights

The Akaki River in Ethiopia is purported to be contaminated with multiple toxic agents, including metals
One study found that manganese and iron levels in the Akaki River exceeded limits set by the Ethiopia Environmental Protection Agency
This study found measurable amounts of cadmium, chromium, copper, zinc, manganese, iron, and nickel in soil and vegetables irrigated by the Akaki River, with all vegetables having chromium levels that exceeded the maximum limit [1]

Summary

Introduction

The Akaki River in Ethiopia is purported to be contaminated with multiple toxic agents, including metals. One study found that manganese and iron levels in the Akaki River exceeded limits set by the Ethiopia Environmental Protection Agency. This study found measurable amounts of cadmium, chromium, copper, zinc, manganese, iron, and nickel in soil and vegetables irrigated by the Akaki River, with all vegetables having chromium levels that exceeded the maximum limit [1]. Another study found that vegetables irrigated by the Akaki River had levels of cadmium and lead that exceeded the maximum limit [5]. Urinary molybdenum (p < 0.001), tungsten (p < 0.001), lead (p < 0.001), uranium (p < 0.001), and mercury (p = 0.049) were higher in Akaki-Kality participants compared to Yeka participants Participants in both subcities had low urinary iodine; 45% met the World Health Organization (WHO) classification for being at risk of moderate iodine deficiency. Toxicity data for many of these metals are very limited

Objectives

Methods

Results

Conclusion