Slags, sponge iron production by coal reduction in retort

Toxicity to birds

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to birds

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

The available identification data for the Target and the Source substance support the read-across hypothesis. Adequate, reliable and available scientific information indicate that the Target and Source substance have, or are very likely to have, similar (eco)toxicological properties. There are no indications that constituents other than those identified for the substances or impurities may influence the validity of the read-across. There is no evidence that additional toxicological mechanisms, other than those identified in the read-across hypothesis, may be acting or have an adverse effect on the validity of the read-across.

Reason / purpose for cross-reference:

read-across source

GLP compliance:

no

Vehicle:

no

Remarks on result:

not determinable

Remarks:

Field study: 10 stations in the Nord-Ostsee-Kanal in the area and vicinity of the Schirrnauer lake (channel km 70 to 75). Observation of bird behaviour

Validity criteria fulfilled:

yes

Conclusions:

Gulls feed indicriminately on eggs, larvae and adult herrings in control stone fields (basalt, granite, and diabase) as well as in slag fields

Executive summary:

No study designed to measure the toxicity of slags on birds was performed. However, there are some coincidentail observations from another field study suggesting that slags do not negatively affect birds.

A field study was conducted in the Nord-Ostsee-Channel to elucidate the effects of stones of slag and natural rock on the reproduction of the herring, Clupea harengus. This channel is a significant spawning ground of herring, and every year approximately 15 millions of adult fish enter the channel for reproduction. The estimated number of eggs is approximately 230000 eggs/m2 of stone field, which equals approximately 83 billions of eggs in the channel (30 km length of embarkment protected with stones, width 6 m). The eggs are deposited above the stone fields, sink to the ground and attach to the stones and the filamentous algae growing on these stones.

From the egg distribution data, it was apparent that herring does not prefer to slag the natural rocks basalt, granite, and diabase as a spawning ground.

The oxygen concentration of egg layers on hard ground (independent on the nature of the stones - slag or natural rocks) was close to saturation level (104 +/- 2 % of saturation, approximately 8 mg/L, depending on e.g. temperature and salinity).

The fertilization rate of eggs was independent from the nature of the stone fields and there was no difference between slag stone fields and the control fields of basalt, granite, and diabase (almost complete fertilization, at least 98.7 %)

The viability of the eggs was determined from the heartbeat of the developping larvae. Almost all larve in the eggs deposited on hard ground had a normal heartbeat (at least 98.3 %). Concomitantly, no deviations from normal development were observed.

Gulls feed heavily and indiscriminately on eggs, larvae and adult herrings in control stone fields (basalt, granite, and diabase) as well as in slag fields

Reference 2

Endpoint:

long-term toxicity to birds

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

Slags are routineously used in the environment and have been tested repeatedly in the laboratory. It has been shown that slags do not exhibit any relevant effect on aquatic or terrestrial organisms. Slags are similar to natural rock. There is no information available which suggests that slags might have a hazardous effect on birds. As no indication of any avian toxicity exists, and also for reasons of animal welfare, it is not recommended to perform a study on the toxicity of slags to birds.

Reason / purpose for cross-reference:

data waiving: supporting information

Description of key information

There is no indication of any hazard of slag to birds, and it has been shown that slags do not exhibit any relevant effect on aquatic or terrestrial organisms. Consequently, no measurements have been done with birds.
In a field study with slags on herring, it was observed coincidently that gulls feed indicriminately on eggs, larvae and adult herrings in control natural rock fields (basalt, granite, and diabase) as well as in slag fields.

Additional information

No study designed to measure the toxicity of slags on birds was performed. However, there are some coincidental observations from another field study suggesting that slags do not negatively affect birds.

A field study was conducted in the Nord-Ostsee-Channel to elucidate the effects of stones of slag and natural rock on the reproduction of the herring, Clupea harengus.

The channel is a significant spawning ground of herring, and every year approximately 15 millions of adult fish enter the channel for reproduction. Billions of eggs are deposited in the channel above the stone fields, and attach to the stones and the filamentous algae growing on these stones.

These eggs and the newly hatched fish larvae are indiscriminately eaten by gulls, and form for some period of the year the feed for large gull flocks which systematically harvest the eggs and larvae in a water depth of up to 40 cm.