Two-generation reproduction study of ethylenediamine in Fischer 344 rats

Safety and efficacy of a feed additive consisting of iron chelate of ethylenediamine for all animal species (Zinpro Animal Nutrition (Europe), Inc.)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of iron chelate of ethylenediamine (Iron-EDA-Cl) as a feed additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) identified several issues related to the data provided concerning the chemical characteristics of the additive. Based on the information provided, the FEEDAP Panel considered unlikely that the additive consists only of iron monochelate of EDA, but of several coexisting (iron) species; therefore, in the absence of adequate experimental data and owing to the uncertainties identified, the Panel cannot conclude on its identity and characterisation. The FEEDAP Panel concludes that the additive is safe for poultry for fattening and reared for laying/breeding, but cannot conclude on the safety for other animal species/categories. The FEEDAP Panel cannot conclude on the safety of the additive for the consumer or the environment. The FEEDAP Panel concludes that handling the additive poses a risk to users by inhalation. The additive should be considered as non-irritant for the skin but irritant for the eyes and skin sensitiser. The FEEDAP Panel cannot conclude on the efficacy of the additive.

Safety and efficacy of a feed additive consisting of manganese chelate of ethylenediamine for all animal species (Zinpro Animal Nutrition (Europe), Inc.)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of manganese chelate of ethylenediamine (Manganese-EDA-Cl) as feed additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) identified several issues related to the data provided concerning the chemical characteristics of the additive. Based on the information provided, the FEEDAP Panel considered unlikely that the additive consists only of manganese mono-chelate of EDA, but of several coexisting (manganese) species; therefore, the FEEDAP Panel was unable to confirm the identity of the additive. The FEEDAP Panel could not evaluate the safety for target species, consumer and environment and the efficacy of the additive owing to the uncertainties and limitations identified in the studies submitted. Concerning the safety of the additive for the users, the Panel considered that handling the additive poses a risk to users by inhalation. The additive should be considered as corrosive to eyes and a skin sensitiser.

Safety and efficacy of a feed additive consisting of zinc chelate of ethylenediamine for all animal species (Zinpro Animal Nutrition (Europe), Inc.)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of zinc chelate of ethylenediamine (Zinc-EDA-Cl) as feed additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) identified several issues related to the data provided concerning the chemical characteristics of the additive. Based on the information provided, the FEEDAP Panel considered unlikely that the additive consists only of zinc mono-chelate of EDA, but of several coexisting (zinc) species; therefore, the FEEDAP Panel was unable to confirm the identity of the additive. The FEEDAP Panel could not evaluate the safety for target species, consumer and environment and the efficacy of the additive owing to the uncertainties and limitations identified in the studies submitted. Concerning the safety of the additive for the users, the Panel considered that handling the additive poses a risk to users by inhalation. The additive should be considered as corrosive to eyes and a skin sensitiser.

Chronic toxicity and carcinogenicity studies of ethylenediamine dihydrochloride by dietary incorporation in Fischer 344 rats

Ethylenediamine dihydrochloride (EDA.2HCl) was incorporated into the diet and fed to Fischer 344 rats for 2 years at target doses of 0, 0.02, 0.10 or 0.35 g/kg/day (equivalent to 0.009, 0.045 and 0.158 g free EDA/kg/day). Two separate untreated control groups were used. Interim sacrifices were at 6, 12 and 18 months and the terminal sacrifice was at 24 months. Under the conditions of this study, EDA.2HCl was not carcinogenic in the Fischer 344 rat. Most toxic responses were observed at the 12-month sacrifice and thereafter. Reductions in mean body weight gain were observed in high dose group male rats throughout most of the study and in the high dose group of female rats after approximately 18 months. Conversely, there was a slight increase in the mean body weight gain for the medium level female rats from about day 21 until 21 months that was of equivocal biological significance. Increased mortality was observed in the high dose group of both sexes and the mid dose group of female rats. The cause of the decreased survival was unclear, but may have been related to the enhancement of background degenerative lesions such as chronic nephropathy. Throughout the study, male rats from the high dose group had decreased erythrocyte counts, haemoglobin concentration and haematocrit. The cause and biological significance of the haematological changes were unknown. Increased water consumption was observed in the high dose group of both sexes during the latter half of the study. Increased urine volume with concurrent decreased urine specific gravity was generally observed in the high dose group of both sexes in the last half of the study and suggested a possible alteration in kidney function. Altered urine volume and specific gravity persisted to termination in female rats only. Slight increases in absolute and relative kidney weights were also observed in the high dose group of female rats during the latter half of the study. Hepatocellular pleomorphism was observed in the high dose group of both sexes, especially the female rats, and may have contributed to increased mean liver weights observed primarily in female rats from the high dose group. Hepatocellular pleomorphism was first observed in female rats at 12 months but was not observed in male rats until the final sacrifice. Rhinitis and tracheitis were observed with greater frequency in the high dose group of male rats at 12, 18 and 24 months and in high dose group female rats at 18 months. At 24 months, rhinitis, but not tracheitis, persisted at a significantly greater frequency in high dose group female rats. The apparent no-observable-effect level (NOEL) of this study was at the lowest dose level, 0.02 g/kg/day (equivalent to 9 mg EDA/kg/day).

Organic acids and bases: review of toxicological studies

Organic acids and bases are among the most frequently used chemicals in the manufacturing industries. However, the toxicology of only a number of them has been fully characterized, and for fewer still have occupational exposure limits been established. This paper reviews the acute and chronic toxicity data of the organic acids and bases, and considers the mechanism by which these chemicals produce their effects. A methodology for establishing preliminary occupational exposure limits based on the physicochemical properties of these chemicals is presented. Workplace exposure limits for 20 organic acids and bases which currently have no exposure guidelines are suggested. Advice regarding appropriate medical treatment of exposure to these materials is discussed.

Biochemical and morphological studies on the percutaneous uptake of [14C] ethylenediamine in the rat

Male Wistar rats were exposed to aqueous [14C]ethylenediamine (EDA) solutions (10, 25, or 50%) percutaneously over a 7 x 7 cm area on the back with occlusion for 24 h. For each rat dosed, three types of studies were conducted: (1) plasma kinetics, (2) material balance, and (3) histological evaluation, including autoradiography of the skin sample from the dosing area. Adequate kinetic measurements were obtained only from animals treated with 25 and 50% EDA, but not from the 10% treatment group, due to analytical limitations. The uptake of [14C]EDA percutaneously by the rat was relatively slow in comparison with uptake following peroral or endotracheal administration. The absorption of EDA by the animals was estimated to be greater than 61, 55, and 12%, respectively, for the 50, 25, and 10% treatment groups. A large portion (11-32%) of the dose was left on/in the dosing area. Urinary excretion was the predominant route for the disposition of EDA. The recovery of the administered dose was low (70-83%), possibly due to volatilization of EDA from the skin during dosing and holding. Histologic examination of skin sections (dosing areas) revealed a normal, intact epidermis in rats dosed with 10% EDA, but full-thickness epidermal necrosis in rats dosed with 25% or 50% EDA solutions. The damage of the epidermis apparently enhanced the penetration of EDA. Autoradiographic preparations revealed a concentration of the [14C]EDA radiolabel over the keratin layer and hair shafts.