What does an LD-50 of 500-5,000 mg/kg suggest?

An LD-50, or lethal dose for 50% of a population, is a standard measure used to assess the toxicity of a substance. It is expressed in terms of the amount of substance (in milligrams) per kilogram of body weight that is needed to cause death in 50% of a test population.

When the LD-50 range is between 500-5,000 mg/kg, it indicates that the substance has a moderate level of toxicity. This range suggests that a relatively higher dose would be needed to reach a lethal effect compared to highly toxic substances which have much lower LD-50 values, meaning they can cause death with smaller amounts.

In contrast, substances that fall into the "slightly toxic" category typically have higher LD-50 values, often above 5,000 mg/kg, indicating that they require a much larger dosage to pose a significant risk of death. Therefore, a range of 500-5,000 mg/kg is recognized as indicative of moderate toxicity rather than slight or non-toxic categories.