Pulse Brain · Growing Health Evidence Index
Tier 3 — Observational / field trialPeer-reviewedConventional

The relation of manure to the nutritive and vitamin value of certain grain

McCarrison, R

British Medical Journal · 1924

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Summary

This 1924 laboratory study attempted to isolate and identify the carcinogenic agent(s) in coal tar by chemical fractionation and testing on mice. Fraction D (higher-boiling compounds) proved more carcinogenic than Fraction C, producing 8 epitheliomas among 30 mice by day 258. The authors concluded that the active carcinogenic substance remains unknown among tested constituents (anthracene, phenanthrene, chrysene, and others), suggesting it may be a previously unidentified compound.

Regional applicability

This is a historical laboratory study on coal tar toxicology conducted in the United Kingdom and published in the British Medical Journal. Its findings are relevant to occupational and environmental health contexts but do not directly address agricultural, soil, or food systems.

Key measures

Tumour incidence and type (epithelioma, papilloma, epithelial horn) in mice exposed to coal tar fractions; nitrogen content measured by Prussian blue test

Outcomes reported

The study tested chemical fractions extracted from coal tar on mice to identify carcinogenic compounds, observing tumour development rates in different fractions over 355 days of observation.

Theme
General food systems / other
Subject
Out of scope / non-food
Study type
Research
Study design
Laboratory animal experiment
Source type
Peer-reviewed study
Status
Published
Geography
United Kingdom
System type
Laboratory / in vitro
DOI
10.1136/bmj.1.3300.567
Catalogue ID
IRmqh56zun-52028c

Topic tags

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