Good Agricultural Practices Water in Field and Packing Shed

Transcription

1 USDA Ellen Phillips Good Agricultural Practices Water in Field and Packing Shed This activity was funded, by Purdue, as part of AgSEED Crossroads funding to support Indiana's Agriculture and Rural Development. Purdue University Cooperative Extension Service is an equal access/equal opportunity institution.

2 Water: Major Source of Contamination for Fresh Fruits and Vegetables Pathogens Found in Water: Escherichia coli Salmonella spp. Cryptosporidium parvum Cyclospora cayetanensis Salmonella on muskmelon E. coli Salmonella

3 Describe the water system Perform a sanitary survey Water sources Water movement onto farm Portable, surface, well Facilities Plumbing: back flow prevention? cross connections? dead end lines? Equipment Irrigation pumps, pipes, lines Water storage tanks Testing Water Sample water close to point of use Water use Irrigation, application Post-harvest Use water of appropriate microbial quality Treatment Keep records of testing and results Purdue Extension Safewater Site

4 Sanitary Survey Run-off from surrounding areas Flooding Liquid manure applications Water Sources Potential upstream sources of contamination Point-source contamination Non-point-source contamination run-off tile drains Resource:

5 Contamination Human or animal feces is the most common source of contamination in water Prevent contamination by proper Personal hygiene Livestock management Manure management

6 Water Sources Public water systems Surface water Ponds, ditches, streams, rivers Wells Open Capped

7 Public Water Systems Least likely to be contaminated Legally must be potable Request copies of water quality tests at least annually

8 Surface Water Most likely to be contaminated Run-off or wind-dispersal from animal facilities or compost operations Improperly treated sewage Wildlife Protecting Surface Water Manage livestock and manure appropriately Upgrade sewage systems (public and private) Reduce run-off Maintain wetlands

9 Wells Less likely to be contaminated Contamination can enter at the well-head Uncapped or improperly capped wells Damaged wellhead or casing risky Protecting Wells Don t mix pesticides or other chemicals near the well Don t apply solid manure near well Use backflow prevention fittings when applying ag chemicals through irrigation system Retire and properly cap abandoned or unused wells Keep livestock away from active recharge area Inspect wells annually Image and reference: Indiana Farmstead Assessment: Drinking Water Well surveys/factsheets/farmassess1.htm Sealed Well Managing the Wellhead Protection Area wellhead/manage.htm

10 Pay Attention to Water Distribution Systems Irrigation system parts How are they stored when not in use? If contaminated, how can they be cleaned? Potential for contamination while in use? Plumbing connections No cross-connections in plumbing system Backflow prevention devices in place No dead-end or unused lines Photo source: yelp.com Purely Water, Lake Hopatcong, NJ

11 Pay Attention to Water Storage Water reservoirs or storage tanks Tanks for hand washing water Cisterns for rainwater collection Nurse tanks for pesticide applicators

12 Testing Water Sources Public water Yearly (obtain tests from water company) Surface water Yearly before use Regularly during use Well water at beginning of season and then every three months

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15 Measuring Water Quality: Microbiological Tests Sample close to point of use. Tests are used to track water quality, not for daily monitoring Records of test dates and results are important to establish patterns Change in pattern may indicate a problem

16 Microbial Tests Presence of indicator organisms means there may be a problem with fecal contamination Indicator organisms: Total coliform Fecal coliform Generic E. coli Reported as MPN/100 ml Most Probable Number per 100 milliliters of sample Generic E. coli is the preferred indicator organism for GAPs

17 Microbial Standards for Water Before Harvest Agricultural water must be safe and of adequate sanitary quality for its intended use Proposed Produce Safety Rule, 2013 Industry standards are based on: EPA drinking water standards or EPA recreational water standards Industry standards vary with commodity

18 Proposed FSMA Rule compliance dates for water quality standards, and related testing and recordkeeping provisions additional two years beyond the compliance dates of the final rule. proposing a tiered and more targeted approach to testing each source of untreated water reduce how often the water is tested, with the frequency depending on the water source (i.e. surface or ground water) and on the results of prior tests. updating the microbial quality standard to reflect data that supports the 2012 Environmental Protection Agency recreational water quality criteria. establishing a sufficient interval of days between last irrigation and harvest to allow time for potentially dangerous microbes to die off. (9/14)

19 Water Quality Before Harvest For water that DOES NOT contact edible portion of the crop: Criteria from Leafy Greens Marketing Agreement (8/4/2010), derived from EPA recreational water standards. Geometric mean of 5 samples Any single sample Generic E. coli MPN/100 ml less than or equal to 126 less than or equal to 576

20 Water Quality Before Harvest For water that DOES or is LIKELY TO contact edible portion of the crop: Generic E. coli MPN/100 ml Geometric mean of 5 samples Any single sample less than or equal to 126 less than or equal to 235

21 Proposed FSMA Water Quality Microbial Standards Summary Before Harvest During/ After Harvest Produce Not Usually Cooked Water Contacts Produce E. coli: mean less than 126 MPN/100 ml. None > 235 E. coli: zero or not detectable Water Does Not Contact Produce or Food Contact Surface no standard no standard Produce Usually Cooked Any Application Method no standard no standard

22 courtesy W. Kline

23 Sampling Water Sources Contact lab before sampling Confirm desired tests available: Generic E. coli MPN for surface water OR test for potable water Request sampling instructions Follow them! Obtain containers Request shipping information Deliver as soon as possible, certainly within 24 hours of sampling Keep samples on ice Create chain of custody forms documents who took the sample time of sample collection time of delivery to the lab

24 Surface Water Test Record

25 Water Testing Methods Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC) International, 18 th ed., rev 4., 2011) Standard Methods for the Examination of Water and Wastewater (21 st ed., 2005), American Public Health Association FDA Bacteriological Analytical Manual (BAM) (8 th ed., rev. A, updated 2011) Or equivalent method

26 Indiana Certified Microbiology Drinking Water Laboratories

27 When Water Source Doesn t Meet the Grade Stop using the water Identify the problem One-time issue or ongoing? Well treatment Chlorine treatment of well. See IDEM recommendations Surface water treatment Chlorine treatment before irrigation Irrigation water treatment: Dosatron injector

28 Water Uses Irrigation Pesticide application Nutrient application Frost protection Postharvest

29 Irrigation Greatest Risk? Water contacting edible portion of crop near harvest Drip Irrigation Lower risk of crop contamination May not wet edible portion of crop High water use efficiency Overhead Irrigation Higher risk of crop contamination Likely to wet edible portion of crop

30 Water used for Pesticide, Nutrient Application and Frost Protection Water used to apply materials to crop should meet the same standards as irrigation water. Nutrients Pesticides Frost protection

31 Preventive Controls Field Water Select the source of water with lowest contamination Use only approved water treatments and follow label instructions Test water quality of water sources Minimize water applied directly to edible part of plant Inspect and clean equipment

32 Postharvest Water Uses Washing Hydrocooling Ice Flumes Dump tanks Hydration Purpose of treating the water prevent cross-contamination by killing microbes in the water Photo credit: Lanes End Farm

33 Water Temperature Water can infiltrate into Produce tomatoes, apples, cantaloupe If water is colder than the product, it is sucked in Any pathogens enter with the water, could spread through the product Most likely when product is submerged in water Keep dump tank water within 10 F of produce core temperature for products where infiltration is likely water 10 F above produce is often recommended

34 Postharvest Water Quality At the start of the process... All water that contacts the crop during and after harvest should meet EPA standards for microbial quality of drinking water(standards for potable water) Test water source Generic E. coli Test negative or below detection limit

35 Postharvest Water Quality Water should be treated before use or reuse if: - doesn t meet microbial standards for drinking water - becomes contaminated during postharvest use Sanitizers for Postharvest Water Chlorine Peroxyacetic acid Ozone UV-C Illumination Source: Suslow, T Postharvest chlorination. Pub. 8003, UCDANR. anrcatalog.ucdavis.edu/pdf/8003.pdf

36 Preventive Controls Postharvest Water If you must use water after harvest: Start with water that meets microbial standards for drinking water (potable water) Consider treatment for single-pass water If water is re-used, remove debris and treat Change water regularly (at least daily is recommended) Monitor sanitizer in water and keep records Keep dump tank water within 10 F of produce core temperature for products where infiltration is likely (water 10 F above produce is often recommended) Use only approved water treatments and follow label instructions

37 Potential Water Contamination: Flooding! We don t always control the water Flood waters may contain Sewage Chemicals heavy metals pathogens FDA considers food contacted by flood water to be adulterated and not fit for human consumption Flooding is the flowing or overflowing of a field with water outside a grower's control FDA Guidance Evaluating the Safety of Flood-affected Food Crops for Human Consumption. Pooled water that is not reasonably likely to cause contamination of the edible portions of fresh produce is not considered flooding. FDA Guidance Evaluating the Safety of Flood-affected Food Crops for Human Consumption.

38 Flood Waters Contact Edible Portion of Crop Do not harvest for food Manage so that the contaminated crop does not contaminate unaffected crops FDA Guidance Evaluating the Safety of Flood-affected Food Crops for Human Consumption.

39 Flooding In or Near Crop Flood Waters do NOT Contact Edible Portion Evaluate on a case-by-case basis for likelihood of contamination " Consider testing for:" Mycotoxins "Heavy metals" Pathogens "Pesticides" PCBs " "Other contaminants" Get technical advice" FDA Guidance Evaluating the Safety of Flood-affected Food Crops for Human Consumption.

40 Prevent cross contamination between flooded and non-flooded areas " Document extent of flooding with photos and markers in field" Clean equipment after use in flooded area" Avoid travelling through flooded area on way to crop" Wear boots, gloves when working in flooded areas" Don t harvest near flooded area (30-ft.)"

41 Flooded Before Crop is Planted Consider field history and crop selection Consider time between the flooding, planting and harvest LGMA recommends 60 days before planting Consider source of flood (drainage ditch, river, etc.) and potential for human pathogens Allow soils to dry; rework before planting Maybe: sample soil for microorganisms ETM: IMG_6211.JPG FDA Guidance Evaluating the Safety of Flood-affected Food Crops for Human Consumption.

42 Notes on Sampling Soil for Microbes in Flooded Fields Sampling does not guarantee that crops are pathogen-free. EPA Soil Screening Guidance: Technical Background Document provides guidelines for sampling (see ch. 4). EPA Standards for the Use and Disposal of Sewage Sludge 40 CFR Part 503 provides criteria for microbial content (see ch.4).

43 Pooled Water Contact with pooled water from irrigation or rainfall should be avoided (ECFS) Reduce potential for contamination from pooled water Protective barriers Staking Change irrigation method FSMA: requires addressing risks of pooled water.

44 Water Recordkeeping Documentation and summary of survey Potable water for workers Source and method of irrigation Sampling location, date, and test results for all water sources Procedures for water treatment Water treatment monitoring records Packing line water temperature records Procedure and records for cleaning of water contact surfaces Documentation of potable water for ice

45 Questions? Purdue University is an Equal Opportunity/Equal Access InsBtuBon Funded in part by a USDA Specialty Crops Block Grant from the Indiana State Department of Agriculture

46 Acknowledgments Por$ons of this presenta$on adapted from the work of: Elizabeth Bihn, NaBonal GAPs Program at Cornell Wes Kline, Extension Agent, Rutgers Liz Maynard, Extension Specialist, Purdue ScoQ Monroe, Extension Educator, Purdue North Carolina State University MarketReady Team NaBonal GAPs Program Par$ally Funded by: Purdue, as part of AgSEED Crossroads funding to support Indiana's Agriculture and Rural Development USDA Specialty Crops Block Grant from the Indiana State Dept. of Agriculture