Asbestos
San Francisco City Water System
Asbestos is a mineral fiber introduced into water by the dissolution of asbestos-containing minerals and from decay of asbestos cement in water mains. Asbestos causes cancer when ingested or inhaled.
20
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | N/A | 0 | 0 | N/A |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 16 | 0 | ND |
| 2019 | ND | 4 | 0 | ND |
MFL = million fibers per liter
State and national drinking water standards and health guidelines
EPA Maximum Contaminant
Level (MCL) 7 MFL
The legal limit for asbestos, established in 1991, was based on toxicity studies in laboratory animals conducted in the 1980s.
MFL = million fibers per liter
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-11 | 9590-007-1115 | ND |
| 2018-03-06 | 9590-004-1031 | ND |
| 2018-03-06 | 9590-008-0914 | ND |
| 2018-03-08 | 9590-006-0925 | ND |
| 2018-04-17 | 9590-007-1055 | ND |
| 2018-06-12 | 9590-004-1058 | ND |
| 2018-06-12 | 9590-008-0930 | ND |
| 2018-06-12 | 9590-006-1012 | ND |
| 2018-07-17 | 9590-007-0519 | ND |
| 2018-09-18 | 9590-006-0945 | ND |
| 2018-09-18 | 9590-004-0855 | ND |
| 2018-09-18 | 9590-008-1025 | ND |
| 2018-10-17 | 9590-007-0730 | ND |
| 2018-12-11 | 9590-006-0915 | ND |
| 2018-12-11 | 9590-004-0845 | ND |
| 2018-12-11 | 9590-008-1045 | ND |
| 2019-06-17 | 9590-006-1206 | ND |
| 2019-06-17 | 9590-004-0956 | ND |
| 2019-06-17 | 9590-007-0905 | ND |
| 2019-06-17 | 9590-008-1106 | ND |