Chromium (total)
Lehigh County Authority Allentown Division
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 1.000 ppb | 2 | 2 | 1.000 ppb |
| 2019 | 1.50 ppb | 2 | 2 | 1.000 ppb - 2.00 ppb |
| 2020 | 0.550 ppb | 4 | 1 | ND - 2.20 ppb |
| 2021 | 3.38 ppb | 4 | 3 | ND - 4.80 ppb |
| 2022 | 13.3 ppb | 4 | 4 | 7.40 ppb - 30.0 ppb |
| 2023 | 1.000 ppb | 5 | 4 | ND - 2.00 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EPA Maximum Contaminant
Level (MCL): 100 ppb
The legal limit for total chromium, established in 1991, was based on a 1958 toxicity study in laboratory animals, and applies to both the less-toxic trivalent chromium and the more-toxic hexavalent chromium forms of this compound. This limit does not protect against the risk of cancer from ingestion of hexavalent chromium.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-08-07 | 8081002-01 | 1.000 ppb |
| 2018-08-07 | 8081002-02 | 1.000 ppb |
| 2019-08-13 | 9076596-02 | 1.000 ppb |
| 2019-08-13 | 9076596-01 | 2.00 ppb |
| 2020-10-12 | 23232317.00 | ND |
| 2020-10-21 | 23232331.00 | ND |
| 2020-10-28 | 23232717.00 | ND |
| 2020-10-28 | 23232705.00 | 2.20 ppb |
| 2021-10-06 | 25456614.00 | 4.80 ppb |
| 2021-10-11 | 25456598.00 | ND |
| 2021-10-13 | 25457002.00 | 4.10 ppb |
| 2021-10-13 | 25456989.00 | 4.60 ppb |
| 2022-10-05 | 27693461.00 | 7.40 ppb |
| 2022-10-05 | 27693449.00 | 7.70 ppb |
| 2022-10-11 | 27693473.00 | 8.00 ppb |
| 2022-10-19 | 27694097.00 | 30.0 ppb |
| 2023-10-11 | 29937627.00 | 2.00 ppb |
| 2023-10-11 | 29937625.00 | 1.000 ppb |
| 2023-10-18 | 29937626.00 | 1.000 ppb |
| 2023-10-25 | 29937665.00 | 1.000 ppb |
| 2023-10-25 | 29937664.00 | ND |