scholarly journals Measuring Submicron-Size Fractionated Particulate Matter on Aluminum Impactor Disks

Radiocarbon ◽  
2010 ◽  
Vol 52 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Bruce A Buchholz ◽  
Paula Zermeño ◽  
Hyun-Min Hwang ◽  
Thomas M Young ◽  
Thomas P Guilderson
Keyword(s):  
Particulate Matter ◽  
Airborne Particulate Matter ◽  
Low Flow ◽  
Airborne Particulate ◽  
Sample Processing ◽  
Thin Aluminum ◽  
Carbon Mass ◽  
Filter Papers ◽  
Processing Techniques ◽  
Gas Leaks

Submicron-sized airborne particulate matter (PM) is not collected well on regular quartz or glass fiber filter papers. We used a micro-orifice uniform deposit impactor (MOUDI) to fractionate PM into 6 size fractions and deposit it on specially designed high-purity thin aluminum disks. The MOUDI separated PM into fractions 56–100, 100–180, 180–320, 320–560, 560–1000, and 1000–1800 nm. Since the MOUDI has a low flow rate (30 L/min), it takes several days to collect sufficient carbon on 47-mm foil disks. The small carbon mass (20–200 μg C) and large aluminum substrate (∼25 mg Al) present several challenges to production of graphite targets for accelerator mass spectrometry (AMS) analysis. The Al foil consumes large amounts of oxygen as it is heated and tends to melt into quartz combustion tubes, causing gas leaks. We describe sample processing techniques to reliably produce graphitic targets for 14C AMS analysis of PM deposited on Al impact foils.

scholarly journals The Impact of Bushfire Smoke on Cattle—A Review

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 848
Author(s):  
Benjamin Eid ◽  
David Beggs ◽  
Peter Mansell
Keyword(s):  
Particulate Matter ◽  
Prolonged Exposure ◽  
Negative Impact ◽  
Airborne Particulate Matter ◽  
Mortality Rates ◽  
Airborne Particulate ◽  
Primary Mechanism ◽  
Background Mortality ◽  
Fire Front ◽  
The Impact

In 2019–2020, a particularly bad bushfire season in Australia resulted in cattle being exposed to prolonged periods of smoke haze and reduced air quality. Bushfire smoke contains many harmful pollutants, and impacts on regions far from the fire front, with smoke haze persisting for weeks. Particulate matter (PM) is one of the major components of bushfire smoke known to have a negative impact on human health. However, little has been reported about the potential effects that bushfire smoke has on cattle exposed to smoke haze for extended periods. We explored the current literature to investigate evidence for likely effects on cattle from prolonged exposure to smoke generated from bushfires in Australia. We conducted a search for papers related to the impacts of smoke on cattle. Initial searching returned no relevant articles through either CAB Direct or PubMed databases, whilst Google Scholar provided a small number of results. The search was then expanded to look at two sub-questions: the type of pollution that is found in bushfire smoke, and the reported effects of both humans and cattle being exposed to these types of pollutants. The primary mechanism for damage due to bushfire smoke is due to small airborne particulate matter (PM). Although evidence demonstrates that PM from bushfire smoke has a measurable impact on both human mortality and cardiorespiratory morbidities, there is little evidence regarding the impact of chronic bushfire smoke exposure in cattle. We hypothesize that cattle are not severely affected by chronic exposure to smoke haze, as evidenced by the lack of reports. This may be because cattle do not tend to suffer from the co-morbidities that, in the human population, seem to be made worse by smoke and pollution. Further, small changes to background mortality rates or transient morbidity may also go unreported.

Sign in / Sign up

Export Citation Format

Share Document