“…Phosphine is rare in the earth's environment because it is easily oxidized by air (WHO, 1988), and is difficult to produce. New analytical developments made it possible to detect small amounts of phosphine in soil, sludge and biogases in the environment (Devai et al, 1984(Devai et al, , 1988Devai and DeLaune, 1995;Eismann et al, 1997;Gassmann and Glindemann, 1993;Gassmann and Schorn, 1993;Gassmann, 1994;Glindemann and Bergmann, 1995;Glindemann et al, 1996a;Han et al, 2000;Iverson, 1968;Liu et al, 1999). Tsubota (1959) found not phosphine but phosphites as reduced phosphorus compounds in a Japanese paddy field.…”