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Is there a risk of foodborne illness from leaving a lunch unrefrigerated for four hours before lunchtime?

There is a risk anytime when perishable food is left at room temperature for more than two hours. To reduce the risk, freeze something to be included with the lunch such as a juice box or a small plastic container of water, which will keep the food cool until lunchtime. A small ice pack that can be frozen, e.g. those used in coolers is also useful.

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