Despite the claims made by manufacturers, available studies which have used scientific methods to investigate these additives have come to the conclusion that long-term beneficial effects are not proven.
[5] Such EM blends include:[6] In his presentational essay "EM: A Holistic Technology For Humankind", Higa states:"I developed a mixture of microbes, using the very common species found in all environments as extensively used in the food industry–namely Lactic Acid Bacteria, Photosynthetic Bacteria an[d] Yeasts (..) EM (..) was developed by accident (..)"[7] The pseudoscientific concept of "friendly microorganisms" was developed by professor Teruo Higa, from the University of the Ryukyus in Okinawa, Japan.
He stated in the 1980s that a combination of approximately 80 different microorganisms was capable of positively influencing decomposing organic matter such that it reverts into a "life-promoting" process.
"Hence 'Effective Microorganisms' will not be able to improve yields and soil quality in mid term (3 years) in organic arable farming.
[16] Due to the fact that only very few studies exist which have used scientific methods to investigate additives based on EM, any claims made by manufacturers regarding long-term beneficial effects need to be evaluated in the intended conditions.
[4][15] Natural yogurt, or sauerkraut juice (pickled sour cabbage) can be successfully substituted for commercial EM-bokashi bran.
[22][23] Scientific methods to investigate applications of wastewater additives have come to the conclusion that long-term beneficial effects are not proven.