What is one limitation of composite samples?

Composite samples are created by combining multiple individual samples taken at different times or locations to provide an average representation of a larger volume or area. One limitation of composite samples is that they may not adequately account for variability in the composition of the sampled material over time or across different sampling locations.

For example, if a water body has fluctuating levels of pollutants due to varying sources or conditions at different times, a composite sample could mask these variations and provide an incomplete picture of water quality. This averaging effect could lead to misleading conclusions about contamination levels, as certain spikes in pollutant concentration might be averaged out and not detected in the composite sample. Understanding this limitation is crucial for environmental compliance and decision-making, as it affects the assessment of potential environmental impacts or the effectiveness of pollution control measures.