Table 1.
List of water contaminants and the maximum contamination level (MCL) set by the US Environmental Protection Agency (EPA).
| Category | Contaminant | MCL | Potential Health Effect for Long Term Exposure | Vibrational Spectroscopy Application |
|---|---|---|---|---|
| Microorganisms | Cryptosporidium | Zero | Gastrointestinal illness | Raman, FTIR |
| Giardia lamblia | Zero | Gastrointestinal illness | Raman | |
| Disinfection by-products | Chlorite | 800 ppb | Anemia, nervous system effects | Raman, NIR |
| Total Trihalomethanes | 80 ppb | Liver, kidney or central nervous system problems, risk of cancer | Raman, MIR, | |
| Disinfectants | Chlorine | 4 ppm | Eye/nose irritation; stomach discomfort | FTIR, NIR, |
| Chlorine dioxide | 800 ppb | Anemia, nervous system effects | Raman, MIR | |
| Inorganic chemicals | Cyanide | 200 ppb | Nerve damage or thyroid problems | Raman |
| Copper | 1.3 ppm | Liver or kidney damage | NIR | |
| Arsenic | 10 ppb | Skin damage or problems with circulatory systems | Raman, MIR, NIR | |
| Organic chemicals | Benzene | 5 ppb | Anemia; decrease in blood platelets; increased risk of cancer | Raman, MIR, NIR |
| Toluene | 1 ppm | Nervous system, kidney, or liver problems | Raman, MIR, NIR | |
| Chlorobenzene | 100 ppb | Liver or kidney problems | MIR | |
| Radionuclides | Uranium | 30 μg/L | Increased risk of cancer, kidney toxicity | Raman |
ppb: parts per billion; ppm: parts per million; FTIR: Fourier transform infrared; NIR: Near infrared; MIR: mid (or middle) infrared.