Bedbugs continue to plague consumers, and now it seems they can take a big bite out of the professionals hired to eradicate them. The state Department of Environmental Protection (DEP) imposed an $860,000 penalty this week against TVF Pest Control of Newark, stemming from the company’s alleged misapplication of pesticides in homes to control bedbugs. The penalty, which the company may appeal, follows an investigation by the state agency that claims at least 50 incidences in which TVF inappropriately employed chemicals not intended for indoor use to eliminate the pests. The chemicals can cause headaches, nausea and vomiting. Beyond the penalty, the state also is seeking to permanently revoke TVF’s pesticide business license.