What is a common symptom of biological toxin exposure?

A common symptom of biological toxin exposure is tingling in the hands or mouth. This symptom specifically indicates a neurotoxic reaction, which can occur after consuming food contaminated with certain biological toxins, often produced by specific types of bacteria or seafood. These toxins can affect the nervous system, leading to sensations such as tingling or numbness.

The other symptoms, while they can result from various medical conditions, are not typically associated with biological toxin exposure. Severe headaches and persistent coughs may be related to other illnesses or environmental factors, while fever and chills usually suggest an infection rather than toxin exposure. Therefore, tingling in the hands or mouth stands out as a distinct sign that helps identify potential poisoning from biological toxins, making it the correct response in the context of this question.