Heptachlor
Overview
A former insecticide, now banned, that persists in the environment.
In Florida, Heptachlor was found in 2 community water systems serving about 875 people. It was measured by 1,551 systems in all, so it was detected in under 1% of the systems that tested for it.
The highest reading relative to the limit was at Paradise Park Condo. Assoc. in Charlotte County, at 2% of it.
Where it comes from: Residue of banned termiticide.
The standards
Enforceable. A utility must stay at or under this.
Health-based, not enforceable. Often lower than the limit, sometimes zero.
California OEHHA PHG (1999).
Health effects the EPA associates with it: Liver damage and increased cancer risk.
The health goal is set on health alone. The legal limit is set as close to it as is technically and economically feasible, so treatment cost and available technology are written into the number a utility is measured against. A system at or under the limit is meeting the standard it is required to meet. Both numbers are shown so the distance between them is visible.
What removes it
Activated carbon removes it well. Compounds like this one bind strongly to carbon rather than passing through, so a properly sized carbon filter is a reliable answer.
Treatment guidance describes the methods generally used for this contaminant. What your own tap actually carries depends on your plumbing and your service line as much as on the utility, which is what a test at the house tells you and an annual report cannot.
Where in Florida
Highest reported levels
Data Sources
These figures describe water as delivered by each utility, not what your home’s plumbing adds after it arrives. Informational; not a substitute for testing your own tap.