Limitations on dose estimation.

N A Esmen

doi:10.1289/ehp.81423

Home/Archive/PubMed

PubMed · 7333257

Limitations on dose estimation.

N A Esmen

View original source ↗Export metadata ↓

Abstract

The process of estimation of dose at a target organ from the measurements of environmental concentration of potentially hazardous agents is theoretically examined. The analysis of the estimation process suggests that the design of any study which aims to find the health effects of an agent or to construct a dose-response relationship from environmental measurements must be fully scrutinized to see whether a representative dose is tractable from such measurements made on the agent or extrapolation from a set of known effects at high dose levels is feasible and desirable.

Explore related subjects

Air Pollutants Dose-Response Relationship, Drug Environmental Exposure Humans Mathematics Models, Theoretical Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

N A Esmen. 1981. Limitations on dose estimation.. https://doi.org/10.1289/ehp.81423

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Stable chloroform emissions in southeastern China: insights from recent observations.

Chloroform (CHCl3) is a short-lived ozone-depleting substance not currently regulated under the Montreal Protocol. Due to the unique meteorological conditions in East Asia, CHCl3 emitted in this region has a greater potential to reach the stratosphere and contribute to ozone depletion. As an essential component of national CHCl3 emissions, southeastern China has attracted increasing attention. However, long-term observational data in this region remain relatively scarce, with no updates since 2020. In this study, we continuously measured atmospheric CHCl3 concentrations at a remote monitoring station in southeastern China from 1 June 2023 to 31 May 2025. Frequent concentration enhancements were observed during the monitoring period, with mixing ratios ranging from 9.3 to 134.1 ppt and an average value of 36.8 ± 19.7 ppt. Back-trajectory analysis indicated that air masses associated with elevated CHCl3 levels primarily originated from coastal industrial provinces in eastern China. Using the Potential Source Contribution Function and Concentration Weighted Trajectory methods, we identified the Yangtze River Delta (Jiangsu, Anhui, and Zhejiang Provinces) and Jiangxi Province as dominant source regions. Emissions of CHCl3 in southeastern China were estimated using the Tracer Ratio Method to be approximately 30.1 ± 5.3 Gg/yr from 2023-06-01 to 2025-05-31, indicating overall stability relative to earlier estimates and no apparent upward trend. These findings provide updated insights into the current status of CHCl3 emissions in southeastern China and highlight the need for continued monitoring and emission assessment of CHCl3 in East Asia, given its unregulated status and implications for ozone layer recovery.

Air Pollutants↗

PubMed1998

Fungal metabolism of nitrofluoranthenes.

Metabolism of 2-nitrofluoranthene (2-NFA), one of the most abundant and genotoxic environmental pollutants in air, and of a mixture of 2-nitrofluoranthene and 3-nitrofluoranthene (3-NFA) was studied using (1) the fungus Cunninghamella elegans ATCC 36112 and (2) rat liver microsomes. The fungal metabolites were separated by reversed-phase high-performance liquid chromatography (HPLC) and identified by 1H nuclear magnetic resonance (NMR) spectrometry, ultraviolet (UV)-visible spectroscopy, and online atmospheric-pressure chemical ionization/mass spectrometry (APCI/MS). The fungus metabolized 82% of 2-nitro-[3H]-fluoranthene to 2-nitrofluoranthene 8-sulfate and 2-nitrofluoranthene 9-sulfate. Metabolism of a mixture of 2- and 3-nitrofluoranthene by C. elegans similarly produced 2-nitrofluoranthene 8- and 9-sulfate and 3-nitrofluoranthene 8- and 9-sulfate as major metabolites. In addition, a glucoside conjugate of 3-hydroxy-2-nitrofluoranthene was tentatively identified by APCI/MS analysis. When rat liver microsomes were incubated with a mixture of 2- and 3-nitrofluoranthene for 1 h, in addition to the trans-7,8- and 9,10-dihydrodiols reported previously for 2-nitrofluoranthene, several novel metabolites were produced including 2-nitrofluoranthene trans-4,5-dihydrodiol and 2-nitrofluoranthene trans-8,9-dihydrodiol, the trans-4,5-dihydrodiol of 3-nitrofluoranthene, and phenolic products of both 2- and 3-nitrofluoranthene. The fungal metabolism of the 2- and 3-nitrofluoranthene mixture was similar to the metabolism of individual nitrofluoranthenes; however, the mammalian metabolism of the nitrofluoranthene mixture showed differences in regioselectivity at positions C4, C5, C8, and C9.

Air Pollutants↗

PubMed1998

An investigation of environmental levels of cadmium and lead in airborne matter and surface soils within the locality of a municipal waste incinerator.

The results of an investigation into the environmental impact of heavy metals in the airborne emissions from the Baldovie municipal waste incinerator, Scotland, are presented. A sampling network of 1-km grid squares covering a 7 x 9 km area was established over the incinerator plant and its surroundings. Surface soil core samples were collected from within each 1 km2 and analysed for cadmium and lead content. The spatial distribution of lead levels in soils showed a marked variation downwind from the Baldovie incinerator in comparison with the background level for the area but remained well within the typical range of lead in rural, unpolluted, British soils. A comparison of the observed levels of lead in local soils, with the predicted downwind long-term ground level lead distribution in air indicates that atmospheric emissions of lead originating from the Baldovie incinerator directly determine concentrations of lead in soils within a radius of 5 km of the incinerator. An empirical relationship between the levels of lead in soils and the long-term levels in air was established. In the case of cadmium, the spatial distribution of the heavy metal showed neither a marked nor extensive contamination of the sampled area around the incinerator and remained within the typical range of cadmium levels in rural, unpolluted, British soils. The work concludes that atmospheric emissions of lead from the Baldovie incinerator significantly determines the local distribution of lead in soils within the immediate vicinity of the incinerator.

Air Pollutants↗