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Environmental Milk and Water Laboratory

Air, food, milk, water, pollen, mold and much more...

Milk and Water Laboratory

(314) 615-8324






Frequently Asked Questions


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


Coliform Presence/Absence


Fecal Bacteria (E. coli)


Heterotrophic Plate Count (total “harmless” microbes)

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)

  • Square

    Other Dairy Testing

  • Water Adulteration

  • Butterfat Content

  • % Solids

  • Accreditations


    FDA - Food and Drug Administration: http://www.fda.gov/


    MDNR - Department of Natural Resources: http://www.dnr.mo.gov/


    EPA - Environmental Protection Agency: http://www.epa.gov/


    Question:  What is the difference between raw milk and pasteurized milk?

    Answer:  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.

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

    Answer:  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.”

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


    FDA Milk Safety and Grade A Pasteurized Milk Ordinance:


    U.S. Department of Health and Human Services Food Safety:


    Centers for Disease Control:


    Question:  Can my well become contaminated with bacteria?

    Answer:  Yes! Well water has no disinfectant. Even one microbe can grow and contaminate the well and the entire water distribution system. Simply opening an unpressurized 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.

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

    Answer:  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.

    Question:  How often should I test my well water?

    Answer:  Saint Louis County Department of Public Health recommends that 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”.

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

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

    Main Office

    Environmental Health Laboratories
    6121 North Hanley Road
    Berkeley, MO 63134
    (314) 615-8324

    North County Office

    21 Village Square
    Hazelwood, MO 63042
    (314) 615-7469

    South County Office

    4562 Lemay Ferry Road
    Saint Louis, MO 63129
    (314) 615-4027

    West County Office

    74 Clarkson/Wilson Center
    Chesterfield, MO 63017
    (314) 615-0929

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

    Answer:  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: http://www.amwater.com/moaw/

    Question:  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: