Chromium (total)
CTWC - Shoreline Region-Guilford System
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | 0.0186 ppb | 36 | 2 | ND - 0.340 ppb |
2015 | ND | 2 | 0 | ND |
2016 | ND | 7 | 0 | ND |
2017 | ND | 3 | 0 | ND |
2018 | ND | 2 | 0 | ND |
2019 | ND | 4 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
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 |
---|---|---|
2014-01-29 | 140130CWCEIOC1 | ND |
2014-01-29 | 140130CWCDIOC1 | ND |
2014-02-10 | 201402110107AM | ND |
2014-02-10 | 201402110093AM | ND |
2014-02-10 | 201402110109AM | ND |
2014-02-11 | 201402120674AM | ND |
2014-02-11 | 201402120438AM | ND |
2014-02-11 | 201402120405AM | ND |
2014-02-11 | 201402120573AM | ND |
2014-02-11 | 201402120403AM | ND |
2014-02-24 | 201402250182AM | ND |
2014-03-05 | 2676IOC1 | ND |
2014-03-05 | 2674IOC1 | ND |
2014-03-05 | 2673IOC1 | ND |
2014-03-05 | 2669IOC1 | ND |
2014-04-08 | 201404090427AM | ND |
2014-04-08 | 201404090510AM | ND |
2014-05-21 | 201405220417AM | ND |
2014-05-21 | 201405220336AM | ND |
2014-06-12 | 8367IOC1 | ND |
2014-06-12 | 8366IOC1 | ND |
2014-08-04 | 201408050418AM | ND |
2014-08-04 | 201408050412AM | ND |
2014-08-04 | 201408050337AM | ND |
2014-08-04 | 201408050384AM | ND |
2014-08-13 | 140915-0115IOC1 | ND |
2014-08-13 | 141007-0044IOC1 | ND |
2014-08-13 | BG93593IOC1 | ND |
2014-08-13 | BG93595IOC1 | ND |
2014-08-25 | 201408260368AM | ND |
2014-08-25 | 201408270547AM | ND |
2014-08-26 | 201408270836AM | ND |
2014-08-26 | 201408270840AM | ND |
2014-08-26 | 201408270820AM | ND |
2014-11-18 | 201411190581AM | 0.340 ppb |
2014-11-18 | 201411190387AM | 0.330 ppb |
2015-02-12 | BH73178IOCR | ND |
2015-02-12 | BH73177IOC1 | ND |
2016-01-11 | BK50862IOC1 | ND |
2016-01-11 | BK50864IOC1 | ND |
2016-01-19 | BK54777IOC1 | ND |
2016-01-27 | BK58355IOCR | ND |
2016-01-27 | BK58354IOC1 | ND |
2016-03-14 | BK78126IOC1 | ND |
2016-06-01 | BN44892IOC1 | ND |
2017-01-18 | BX31347IOC1 | ND |
2017-03-08 | BX82062IOC1 | ND |
2017-06-07 | BY34926IOCR | ND |
2018-03-30 | CA11463IOCR | ND |
2018-03-30 | CA11466IOC1 | ND |
2019-01-30 | IOC1 200520057 | ND |
2019-02-27 | IOCR 200523002 | ND |
2019-06-24 | IOC1 200537625 | ND |
2019-07-10 | IOC1 200539998 | ND |