Environmental Testing Services

Drinking Water Analysis by EPA 531.2


EPA 531.2 is used to determine the concentrations of Carbamates in drinking water.


EPA 531.2 is performed using high performance liquid choromatography (HPLC) and post-column reaction to form compounds that are quantitated using a fluorescence detector.

Holding Time

Samples have a 28-day holding time. Samples not analyzed within this period must be discarded and replaced.

Container and Preservative

Collect all samples in 40-mL amber vials which contain 5 mg of sodium thiosulfate crystals (STS) and 375mg of potassium dihydrogencitrate (PDC). STS must be added to each sample to avoid the possibility of reactions that may occur between residual chlorine and indeterminate contaminants present in some solvents, yielding compounds that may subsequently interfere with the analysis.

Shipping/Transport Instructions

Samples must be protected from light and chilled to >0°C to ≤10°C within the first 48 hours after collection and kept at >0°C to ≤6°C after that. Field samples that will not be received at the laboratory on the day of collection must be packaged for shipment with sufficient ice to ensure that they will be >0°C to ≤6 or 10°C upon arrival at the laboratory, depending on arrival time.

Analytes and Reporting Limits

Analytes included on our State of Michigan Drinking Water Certification are designated as such.

  Michigan Certified
  Michigan does not offer certification
  Please request additional information on test


Analyte CAS Number Reporting Limit MI Cert
Aldicarb Sulfoxide 1646-87-3 0.5 μg/L
Aldicarb Sulfone 1646-88-4 0.5 μg/L
Oxamyl (Vydate) 23135-22-0 0.5 μg/L
Methomyl 16752-77-5 0.5 μg/L
3-Hydrocarbofuran 16655-82-6 0.5 μg/L
Aldicarb 116-06-3 0.5 μg/L
Carbofuran 1563-66-2 0.5 μg/L
Carbaryl (Sevin) 63-25-2 0.5 μg/L