Fish Testing

Overview

The presence of persistent toxic substances (PTS) in aquatic ecosystems is a major environmental policy concern for the Great Lakes States.  Contaminated fish are the primary source of chemical exposure for most humans, leading to fish consumption advisories.  The Michigan Department of Health and Human Services (MDHHS) collaborates with the Department of Environment, Great Lakes and Energy (EGLE) on the Michigan Fish Contaminant Monitoring Program (FCMP) to assess chemical contamination in fish from the state's surface waters.  The data collected helps determine if fish from these waters are safe for human and wildlife consumption and serves as an indicator of bio accumulative contaminants in surface water.

The Environmental Inorganic Unit tests homogenized fish tissue samples for mercury (organic and inorganic) and other metals upon request.  These testing methods are based on the Environmental Protection Agency's (EPA) methods 200.11 and 7473.

Methodology

The total mercury (organic and inorganic) is determined without chemical pretreatment using thermal decomposition/atomic absorption spectrophotometry (TD/AA) technology. For all other fish metal analysis, the laboratory analyzes homogenized fish samples using inductively coupled plasma triple mass spectrometry (ICP-MS). 

Sample Instructions

The method used to collect fish must avoid metal contamination.  Individual tissue samples should be taken from fresh, not previously frozen, fish and soon after the fish after collection.  If immediate sampling is not feasible, each fish should be placed in a plastic bag, sealed, and kept on ice or refrigerated at 4°C.