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Milk and Water Laboratory

Milk and Water Laboratory
Air, food, milk, water, pollen, mold and much more...

Milk and Water Laboratory


Services – Microbiological Analysis of Public Drinking Water (including private wells)

  • Coliform Presence/Absence
  • Fecal Bacteria (E. coli)
  • Heterotrophic Plate Count (total “harmless” microbes)

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Services – Dairy Product Testing

  • Petrifilm™ Aerobic Count
  • Petrifilm™ Coliform
  • Pasteurized Milk Containers
  • Antibiotics (Delvo P-5 Pack, IDEXX Snap, Charm SL-BL)
  • Direct Microscopic Somatic Cell Count and Electronic Somatic Cell Count
  • Dairy Process Water (certified through state USEPA program)
  • Homogenization Effectiveness -- Phosphatase (Fluorophos ALP)
  • Dairy products tested include:
    • Raw milk (cow, goat, sheep)
    • Finished Products (cream, half & half, cottage cheese, flavored milk, pasteurized milk, eggnog)
  • Other Dairy Testing
    • Water Adulteration
    • Butterfat Content
    • % Solids

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  1. FDA - Food and Drug Administration:
  2. MDNR - Department of Natural Resources:
  3. EPA - Environmental Protection Agency:

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What is the difference between raw milk and pasteurized milk?

Raw milk is bottled directly from the animal. Pasteurized milk has gone through a rigorously timed process of heating and cooling to specified temperatures in properly maintained and operated equipment. Pasteurization kills potentially harmful bacteria.

Does “organic” pasteurized milk differ from regular cow’s milk.

Organic milk has the same composition, nutritional value, and wholesomeness or safety as regular homogenized milk. Rather, it is normal milk obtained from organically pastured cows under the “Organic Food and Production Act of 1990.”

Where can I find additional information about milk and milk product safety?

FDA Milk Safety and Grade A Pasteurized Milk Ordinance

Can my well become contaminated with bacteria?

Yes! Well water has no disinfectant. Even one microbe can grow and contaminate the well and the entire water distribution system. Simply opening an un-pressurized plumbing system for repair, or opening a faucet while the well pump is turned off, may cause back-siphoning of contaminated water and air at the tap resulting in the contamination of the entire plumbing system. You must keep your faucet aerators clean and free of scale, and replace corroded spigots; chlorine cannot reach bacteria hiding there. Keep taps closed during power outages. If draining pipes for plumbing repair or winterizing, the system must be shock chlorinated when placed back in service.

What should I do if my well water tests “Unsatisfactory” for bacterial contamination?

Bacterial contamination of a residential well and plumbing system requires disinfection by shock chlorination with unscented household laundry chlorine bleach. Saint Louis County Public Health will provide instructions along with the test results.

How often should I test my well water?

We recommend you test your well water yearly, or after plumbing work, power outages, flooding, or you notice a change in water quality. If your water tests “Unsatisfactory”, The Environmental Health Laboratories will provide you with instruction on disinfecting your well and distribution system by shock-chlorination. Your water is safe to drink when it tests “Satisfactory”.

Where can I pick up a sample bottle for water testing?

Sample bottles and instructions for taking water samples may be picked up from 8:00 a.m. to 4:30 p.m. Monday through Friday at the following locations:

Main Office

Environmental Health Laboratories
6121 North Hanley Road
Berkeley, MO 63134

DPH Environmental Health Laboratories
West County Office

74 Clarkson/Wilson Center
Chesterfield, MO 63017

St Louis County - West County Office
South County Office

4562 Lemay Ferry Road
Saint Louis, MO 63129

St. Louis County South County Office
North County Office

715 Northwest Plaza Dr.
St. Ann, MO 63074
RelayMO 711 or 800-735-2966

St. Louis County North County Office

Where can I find data on Saint Louis County’s municipal drinking water?

Public water supplies are required to provide annual Consumer Confidence Reports to their customers. Missouri American Water Company customers receive their reports by mail, or you may view the report at any time on the Internet at:

Where can I find more information on water quality assurance?

EPA Ground Water and Drinking Water

EPA Safe Drinking Water Act

EPA Private Drinking Water Wells

Water Quality Report for St. Louis County

St. Louis County Basic Water Quality Summary