What does the EPA registration number on pesticide labels indicate?

The EPA registration number on pesticide labels indicates that the product has undergone a thorough evaluation process by the Environmental Protection Agency to ensure it meets safety and efficacy standards. This number serves as proof that the product has been registered and approved for use by the EPA, which involves assessing the potential health risks to humans and the environment as well as the effectiveness of the pesticide in controlling targeted pests.

Understanding this, it's clear that the registration number doesn't reflect the quality or pricing of the product (which are more subjective measures), nor does it directly signify an assessment of environmental impact. The focus of the EPA's approval process is primarily centered on safety and effectiveness, making this the correct interpretation of the EPA registration number.