Ashes from fluidized Bed combustion coal fired Power stations with and without co-combustion of secondary fuels (biomass; other fuels - to be verified in view of ecotoxicological and toxicological tests)

Endpoint summary

Description of key information

The test substances, Fluidized Bed Combustion (FBC) Bottom Ash and Fluidized Bed Combustion (FBC) Fly Ash, were tested for subchronic toxicity using the Method B.26 Sub-Chronic Oral Toxicity Test: Repeated Dose 90-day Oral Toxicity Study in Rodents, Council Regulation (EC) No. 440/2008, Published in O.J. L142, 2008. 
No studies on repeated dose dermal toxicity and repeated dose inhalation toxicity of Fluidized  Bed Combustion Ashes are available.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

200 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Additional information

Fluidized Bed Combustion (FBC) Fly Ash

The oral administration of the substance, Fluidized Bed Combustion (FBC) Fly Ash, to rats by gavage for a period of 90 consecutive days at dose levels 50, 200 and 800 mg/kg/day caused significant changes of haematological (haematocrit, haemoglobin, MCV, total leucocyte count, monocytes portion) and biochemical parameters (albumin, sodium). The urinalysis demonstrated effect of the test substance on properties of urine (pH, presence of leucocytes). The test substance had effect on microscopical structure of liver (focal fatty changes).

The value of NOAEL for MALES and FEMALES was established as 200 mg/kg/day.

 

Fluidized Bed Combustion (FBC) Bottom Ash

The oral administration of the substance, Fluidized Bed Combustion (FBC) Bottom Ash, to rats by gavage for a period of 90 consecutive days at dose levels 50, 200 and 800 mg/kg/day had effect on haematological parameters (differential leucocyte count, changes of red cell parameters, changes in haemocoagulation), water consumption and properties of urine (pH, presence of protein and leucocytes). The substance treatment had influence on liver (changes of some biochemical parameters, changes of macroscopical and microscopical structure of liver - vacuolation of hepatocytes).

The value of NOAEL for MALES is 200 mg/kg/day. The value of NOAEL for FEMALES is 800 mg/kg/day.

 

Changes observed after repeated dose oral exposure were similar in both Ashes. Absorption of (FBC) Ashes from the digestive system and their distribution throughout the body of experimental animals to relatively distant compartments was confirmed during oral repeated dose studies. Minerals and metals of (FBC) Ashes are absorbed largely in small intestine. No digestive tract irritation was noted.

 

No studies on repeated dose dermal toxicity and repeated dose inhalation toxicity of Fluidized Bed Combustion Ashes are available.

Repeated dose toxicity: via oral route - systemic effects (target organ) digestive: liver

Justification for classification or non-classification

The data from Study No. 65/09/8:Fluidized Bed Combustion (FBC) Fly Ash-Repeated Dose 90-day Oral Toxicity Study;VUOS-CETA Report No.: 10132, 2010 and from Study No. 66/09/8: Fluidized Bed Combustion (FBC) Bottom Ash - Repeated Dose 90-day Oral Toxicity Study; VUOS-CETA Report No.: 10133, 2010 are of acceptable quality for classification of substances for STOT RE.

The values of NOAEL was used in weight of evidence approach based on a comparison with classification criteria.

The Guidance Values (dose/concentration) for STOT RE Category 1 is C ≤ 10 mg/kg body weight/day, the Value Ranges (dose/concentration) for STOT RE Category 2 is 10 < C ≤ 100 mg/kg body weight/day for oral route exposure (Regulation (EC) No.1272/2008).

The lowest value of NOAEL (200 mg/kg body weight/day) is above the Guidance Values and Range (C).

Based on results of Repeated Dose 90-day Oral Toxicity Studies Fluidized Bed Combustion (FBC) Bottom Ash and Fluidized Bed Combustion (FBC) Fly Ash do not have to be classified as specific target organ toxicants following repeated exposure.