CCA News & Information Articles

Arsenic speciation in multiple metal environments II. Micro-spectroscopic investigation of a CCA contaminated soil. 05-01-2008 The significant co-localization and chemical speciation of As with Cu suggest that the speciation of As in a contaminated soils is not solely controlled by surface adsorption reactions, but significantly influenced by the co-contaminating metal cation fraction. Future studies into As contaminated soil therefore need to focus on identifying the speciation of As and the co-localizing metal cations. full article available to purchase at link Inorganic arsenic speciation in soil and groundwater near in-service chromated copper arsenate-treated wood poles 04-25-2008 Hey Everybody, As this study may seem a bit technical for most lay people I would like to walk you through the results because I believe they affect a great many of us. CCA telephone poles are a cause of heavy metal pollution, arsenic most notably. When you take a test of soil near a cca structure you take soil from the top two ot three inches near a vertical post or underneath the structure. This allows you to test the runoff. With cca treated poles you would take the soil sample in the first two or three inches at the base of the pole. Because the pole is vertical all of the runoff and leaching will be at the base and depending on foot traffic etc it may build here as shown below. Now this study shows differences in the soil types ability to absorb that runoff. Iron is capable of pulling arsenic so surface levels where iron is found are much lower. This is also why mulch coated with iron oxide is also a problem as the iron dust will pull( the red colouring) the arsenic leaching from any treated wood that may be in the mulch. Unfortunately there is often treated wood in mulch. That is because as it ages it is undecernable with the naked eye from natural wood. Back to the poles. The base of these poles present with various levels of arsenic. If you have one on your property or at your child’s school or place of work then you need to be very careful. Children should be taught not to play near them, touch them or the soil around them. People should be very careful when cutting grass as the dust raised will be very toxic. Children and teenagers are often the ones cutting grass to earn money or as part of their chores. This is one exposure than is often missed. I see my neighbor cut around her cca pole and the dust she raises is amazing. I have tried to warn her but she believes it wouldn’t be there if it were a problem. So please take precaution if you must cut around these poles. Keep animals and children away. Also we all know what dogs use poles for and they will be tracking the arsenic into your home. When cutting near these poles wear a proper safety approved mask not a dust mask and shower afterward and please remove your clothes before going indoors and wash them separately. Close your windows also if you are cutting grass anywhere near one. Preferably it would be better to not grow grass there or leave it uncut. Take care everybody and please keep safe. deborah A mass balance approach for evaluating leachable arsenic and chromium from an in-service CCA-treated wood structure. 12-11-2006 The amounts of arsenic found in the infiltrated water below the CCA-treated deck represented 6% of total arsenic leached and less than 0.7% of the initial mass in the wood. The study demonstrated that exposure of a CCA-treated deck to rainfall resulted in elevated arsenic concentrations in both runoff and soil. Although only a relatively small fraction of the initial arsenic from the wood was found to infiltrate through the soil, these impacts were significant and caused the infiltrated water to exceed drinking water standards. The study suggests that potential exposures to arsenic exist indirectly through an environment that is contaminated with arsenic leached from in-service CCA-treated wood. Distribution and mobility of chromium, copper, and arsenic in soils collected near CCA-treated wood structures in Korea. 03-15-2007 Arsenic was more mobile in soil than chromium and copper. The concentration gradient of arsenic in soil was observed only to the depth of approximately 5 cm in one year of outdoor exposure, whereas chromium and copper apparently remained near the surface (approximately less than 1 cm) after their release. Future efforts should be made to observe seasonal impacts on the release of metals and incorporate metal speciation into determining more detailed mobility and distribution. Effects of incising on treatability and leachability of CCA-C-treated eastern hemlock. (Solid Wood Products).(Statistical Data Included) 02-01-2002 Incising is used to increase exposed wood surface and improve uptake and penetration of preservative during pressure treatment of refractory species. However, incising may also cause increased leaching of preservative when the wood is placed in service Effect of humic acid on leaching of CCA from treated wood 01-01-2001 Résumé / Abstract It is known that organic acids are effective at extracting chromated copper arsenate (CCA) components from wood, so the effect of natural humic acids on leaching was studied in the laboratory and in poles in service. Comparative analysis of poles of similar ages was done between those in wet, boggy sites and dry sites. Laboratory leaching studies done according to American Wood Preservers' Association (AWPA) Standard E-11-97 indicated that relatively high concentrations (1,000 to 10,000 ppm) of humic acids increase the leaching of chromium and copper from CCA-C treated wood, and that copper was most affected. They also showed that leaching with natural water samples resulted in higher leaching of all components than leaching with distilled water. Evaluation of CCA component retentions and mass balances in the 5-mm surface of poles in service showed that copper and arsenic were leached significantly from the portions of the poles in contact with water in wet sites. Arsenic losses increased more with pole age compared to the other components. Chromium leaching did not appear to be affected by location in the pole or by site. Although regression analysis showed that the concentration of CCA components in water near poles in wet sites increased with higher natural humic acid concentrations and lower water pH, CCA component levels and mass balances in the wood surface in contact with water in service did not confirm that these factors increased surface leaching