Estimation of cadmium load on Japanese farmland associated with the application of chemical fertilizers and livestock excreta

Abstract

In the present study, we estimated the cadmium (Cd) load on Japanese farmland originating from chemical fertilizers and livestock excreta. Phosphate and compound fertilizers, except for fused phosphate, contained higher concentration of Cd than the other fertilizers. Cadmium concentrations in phosphate fertilizers, cattle excreta, pig excreta, and chicken excreta were 0.04 to 5.30, 0.38, 0.50, and 0.57 mg Cd kg-1, respectively. Cadmium load associated with the application of chemical fertilizers and livestock excreta amounted to 7.034 and 2.161 Mg Cd year-1 in 1997, respectively, indicating that chemical fertilizers were the main source of Cd load on Japanese farmland. Cadmium in non-utilized livestock excreta amounted to 1.408 Mg Cd year-1 in 1997. Phosphate application derived from non-utilized livestock excreta instead of chemical fertilizers increased the Cd load level <1%. Cadmium load associated with the application of chemical fertilizers and livestock excreta accounted for 0.4% of the estimated amount of total Cd in farmland soil (2,216 Mg Cd). It was considered that the risk of an increase in the Cd concentration would be high in farmland with multiple cropping, especially in the case of vegetable and industrial crop cultivation.Key Words: cadmium, chemical fertilizers, livestock excreta, load.Cadmium (Cd) is a toxic substance that reduces crop yield by contaminating farmland soil. It can cause kidney disorders and softening of bones in humans , and is considered to be an endocrine disruptor (Le Gueve1 et al. 1998). Therefore, Japanese law regulates the Cd concentration in soil and food. For example, brown rice that contains more than 1 mg kg-1 of Cd cannot be sold on the market and farmland is designated as contaminated area when brown rice with > 1 mg kg-1 of Cd was produced. It is well known that Cd contamination has been caused by drainage water from mines (Notoya and Sasaki 1988) and sewage sludge (Matsumoto and Hirayama 1990;Fukata et al. 1991;Ito 1991;Sasaki et al. 1991). Although Cd the concentration in both ordinary and contaminated farmlands has been investigated in Japan, data on the Cd load on Japanese farmland associated with the application of chemical phosphate fertilizers and livestock excreta are limited.Our objective was to investigate the annual Cd load on Japanese farmland originating from chemical fertilizers and livestock excreta for 1997, as an extension of the study of Mishima et al. (2003) on phosphate flow for 1997, because it is well known that the Cd load is as sociated with phosphate use (Sugo 1977;Zanders et al. 1999) and there are no data about the total amount of chemical fertilizer use for types of crops as well as livestock excreta use and disposal on a fresh or dry weight basis. We also compared the Cd load with the estimated total Cd amount in farmland soil to examine the potential of an increase in the Cd concentration. Materials and methodsQuantitative analysis of Cd in chemical fertilizers. Seventy-two fertilizers (7 types of fertilizers containing only nitrogen or...

Estimation of Zinc and Copper Balance in Japanese Farmland Soil Associated with the Application of Chemical Fertilizers and Livestock Excreta

“…The amount of Zn and Cu per P,O, were calculated from the sum of Zn and Cu in each type of fertilizers divided by the sum of the amount of P,O, in these fertilizers. Using these values, Zn and Cu doses in relation to chemical fertilizer use were estimated from P,Os application to 6 types of crops (paddy rice, cereals, vegetables, orchard, industrial crops and forage crops) as indicated by Mishima et al (2003), because the amounts and types of fertilizers applied to crops were unknown.…”

“…Zinc and Cu concentrations in livestock excreta were estimated based on the amount of total, utilized as manure and disposed P,O, in livestock excreta from each type of livestock (dairy cattle, beef cattle, pig, layer, broiler) (Mishima et al 2003) and the Zn and Cu concentrations per P,O, were estimated in livestock excreta according to Orihara et al (2002). This was because PzOs, Zn and Cu are not volatile and reducible during composting.…”

“…The objective of our study was to investigate the annual Zn and Cu balance in farmland soil associated with chemical fertilizer and manure application and crop yield in Japan for 1997, as an extension of the study of Mishima et al (2003) on phosphate flow, because it is generally recognized that Zn and Cu in chemical fertilizers originated from phosphate rock (Koshino 2001) and that there are no consistent datasets for fertilizer use for each type of crop and livestock excreta use.…”

Phosphorus conventional use, reduction potential, and possibility of self-sufficiency during food and feed production in Japan

“…However, organic waste is sometimes polluted by heavy metals (cadmium, zinc, copper, etc.) [11,12]. Therefore, application of organic waste compost needs caution or sometimes prohibition to prevent soil pollution.…”

Long-term fertilization with pig-biogas residues results in heavy metal accumulation in paddy field and rice grains in Jiaxing of China

“…HM contamination of agricultural soil caused by animal manure fertilization has been widely reported (Nicholson et al 1999(Nicholson et al , 2003Cang et al 2004;Mishima et al 2004;Dach and Starmans 2005;Li et al 2007). However, with the popularization of biogas projects, less and less animal manure is used directly as a fertilizer for crops and vegetables, while PBR is replacing animal manure used as fertilizer.…”