 In this module, we will address the seed treatment process. If seeds for sprouting have been grown under good agricultural practices and stored and transported in closed containers, the likelihood that they will be contaminated with pathogenic bacteria will be minimized but not eliminated. Seeds for sprouting should be treated with one or more treatments that have been approved for reduction of pathogens. Some treatments can be applied at the sprouting facility, while others will have to be applied earlier in the seed production process. However, at least one approved antimicrobial treatment should be applied immediately before sprouting. Antimicrobials are either pesticides, chemicals, or food additives. As such, their use on seeds for sprouting should be approved by the U.S. Environmental Protection Agency or the U.S. Food and Drug Administration. Permits for use may be needed. Growers should check with their local officials. The goal of treating seeds is to significantly reduce pathogens that may be present on seeds. The primary pathogens of concern are Salmonella and E. coli 0157H7. Salmonella has been recovered from seeds and from seeds sprouted in a sterile environment. Salmonella was the cause of 11 of the 13 reported outbreaks associated with sprouts from commercial growers. The remaining two were caused by E. coli 0157H7. Treatment of seeds in a solution of calcium hypochlorite prepared to contain 20,000 parts per million, or PPM of active chlorine, is recommended. Calcium hypochlorite is specified rather than sodium hypochlorite or domestic bleach because it doesn't significantly reduce permanent germination for most seed types. In recent outbreaks of illness associated with alfalfa sprouts, none of the sprouters could document the use of 20,000 PPM of chlorine to treat seeds. Calcium hypochlorite is the only chemical treatment currently approved by the EPA for disinfecting seeds intended for sprouts at concentrations that can significantly reduce the level of pathogens on seeds. All chemicals used for cleaning and sanitizing, including calcium hypochlorite, should be stored away from areas used for seed storage and sprout production. Storage and handling of chemicals always should be in strict accordance with the label directions for the safety of both consumers and workers. Calcium hypochlorite concentrate, obtained from the manufacturer, as well as the 20,000 PPM treatment solution, are chemical hazards. Again, anyone handling this chemical must follow the label directions and take appropriate precautions. Waterproof gloves, chemical resistant footwear plus socks, protective clothing such as coveralls over a long sleeve shirt and long pants, and protective eyewear and chemical resistant head gear for overhead use are essential to protect handlers from hazards associated with calcium hypochlorite. Additional precautionary measures are identified on the chemical label. A fresh solution of calcium hypochlorite should be used for each batch of seeds. Prepare a 20,000 PPM active chlorine solution by mixing 4.1 ounces of calcium hypochlorite powder, which contains 65% available chlorine with one gallon of potable water at room temperature in a well ventilated area. It's important to weigh the calcium hypochlorite on a scale rather than using a measuring cup. Only by using scales can the proper concentration 20,000 PPM of active chlorine be assured. The solution should be stirred for at least 5 minutes to maximize free chlorine in the solution. Pre-wash seeds in potable water for at least 5 minutes with agitation and then drain the wash water. Treat pre-washed seeds once by soaking 5 pounds of seed in one gallon of 20,000 PPM calcium hypochlorite solution with continuous agitation for 15 minutes at room temperature. After treatment, drain the solution and rinse the seeds thoroughly with potable water for 10 minutes, changing the water several times as necessary. Used calcium hypochlorite solution should be diluted with at least an equal amount of water before disposal. For requirements in your state, contact the State Water Board or the Regional Office of the U.S. EPA. The active chlorine concentration should be measured at least weekly to assure that the desired 20,000 PPM level is present in the treatment solution. The hardness and pH of water used to prepare a calcium hypochlorite solution can affect the concentration of active chlorine and may have to be modified if not within acceptable ranges. Hardness results from minerals, especially calcium and magnesium in water. The pH is a measure of acidity or alkalinity. The pH of the prepared hypochlorite solution should be between 6.2 and 6.8. Measurement of the concentration of active chlorine and pH of the solution should be taken from at least one batch per week. Commercial laboratories are available to provide this service. If results are outside the accepted range, guidance should be sought from the laboratory. Research is underway to develop and evaluate other methods such as extraction of seeds. These include chemicals, temperature control, irradiation, and a combination of these methods. However, none of these treatments are currently validated. That is scientifically proven effective and are not currently authorized or accepted for use on seeds by the FDA and the EPA.