What does a lower LD50 number indicate about a pesticide?

A lower LD50 number indicates that a pesticide is more toxic, meaning that it requires a smaller amount of the chemical to cause harm or lethality to organisms. The LD50, or lethal dose for 50% of the test population, is a standard measure for assessing the toxicity of a substance. When the LD50 value is low, it signifies that the substance poses a greater risk to both target and non-target species, including humans and other wildlife.

While the other options might seem plausible, they do not accurately reflect the implications of a low LD50. A lower LD50 does not mean the pesticide is safer or more environmentally friendly; rather, it indicates increased danger and toxicity. It is essential for users of pesticides to understand this relationship, as it informs safe handling practices, application strategies, and overall risk assessments associated with pesticide use.