Several chemicals follow a threshold dose-response curve, where no response is observed up to a particular threshold and after that dose level, adverse effects increase with the increasing dose. This threshold is considered the point of departure and the driver for hazard assessments. Often in hazard assessments, the point of departure is the dose, from experimental or observational data, where no adverse effects were observed (NOAEL) and bound to the incremental dosing of the study. However, with statistical models, the point of departure can be estimated from the data unrelated to the incremental doses used in a study with confidence limits on the estimated dose. These methods of point of departure estimation are suggested by the National Academy of Science for quantitative hazard assessments.
Waterborne Environmental scientists are adept at determining the point of departure based on a possible toxicants dose response data. We have toxicology, exposure science and statistical experts working together to determine the biologically relevant and statistically defensible point of departure that accurately describes the toxicity data.
The development of a non-cancer or cancer health risk level requires expertise in several areas with a strong understanding of the mechanism of toxicity for the substance in question. Several mathematical techniques and tools are employed to better understand the dose-response relationship of a given chemical. However, without considerable expertise in toxicology, these models could produce a point of departure that is not descriptive of the chemicals threshold. Waterborne has experts in statistics, risk assessment and toxicology to understand a chemicals’ adverse effects and develop a health risk value that is reflective of the chemicals toxicity data.
Our work has included comprehensive exposure and toxicological assessment chemicals of concern, mathematical modeling, identification of data gaps and development of toxicological testing study plans in the event data gaps exist. Waterborne’s toxicologists are well versed in regulatory guidance and requirements in order to provide a defensible quantitative hazard or risk assessment.
Questions about quantitative hazard assessment’s?
Contact Nikki Maples-Reynolds at Maplesfirstname.lastname@example.org.