Which condition should be monitored following a chemical contamination?

Monitoring animal behavior following a chemical contamination is crucial because animals often exhibit changes in behavior in response to environmental hazards, including chemical agents. These changes might include unusual agitation, lethargy, or abnormal movement patterns, which can indicate the presence of harmful substances in the environment. Observing animals can serve as an early warning system, helping to confirm the presence of contaminants that could also affect humans and the environment.

The other choices, while they may have some relevance in different contexts, do not specifically provide the same level of insight regarding immediate toxicological effects following a chemical contamination scenario. For instance, temperature changes could indicate broader weather patterns but may not directly reflect chemical exposure. Wind direction is important for understanding the spread of contaminants but doesn't provide information on the impact of the contamination itself. Humidity levels might affect the behavior of some chemicals but are not as immediate or direct of a hazard indicator as observing animals. Therefore, focusing on animal behavior is a more effective approach for assessing the situation after chemical exposure.