Wood Preservative Chemicals

Exposures to pesticides by pregnant women are well known to result in offspring with birth defects. The following examples are illustrative  

In a case report, a mother who applied DEET daily during her entire pregnancy gave birth to a child with craniofacial dysmorphology, mental retardation, and sensorimotor impairment. I20 

Elevated risks of neural tube defects and other deformities were associated with maternal residence in proximity to agricultural pesticide applications in a California study. The risks were associated with amide, benzimidazole, methyl carbamate, or organophosphorus pesticide use. The risks were found to be greater when increasing numbers of pesticides were applied.  

In a study in rural South Africa, a case control study was conducted to investigate the association between pesticide exposure and the occurrence of birth defects. It was found that women who were exposed to pesticides in gardens and fields were seven times more likely to give birth to babies with birth defects than women not so exposed. Deformed babies were also almost twice as likely to be born when their mothers dipped livestock in pesticides to prevent ticks and 6.5 times more likely to be born when their mothers fetched water with plastic containers that had previously held pesticides than cohort mothers who did not dip livestock or use pesticide-contaminated water containers.  

A study in Washington state found that maternal exposure to agricultural chemicals (fertilizers and pesticides) produced an elevated risk of limb defects)23  

---

Goerlitz DF, Troutman DE, Gody EM, et al. 1985. Migration of wood-preserving chemical in contaminated groundwater in a sand aquifer at Pensacola, Florida. Environ Sci Technol 19 955-961. 

Lamar, R.T. Glaser, J.A. (1994). Field evaluations of the remediation of soils contaminated with wood-preserving chemicals using lignin-degrading fungi. In Bioremediation of Chlorinated and Polycyclic Aromatic Hydrocarbon Compounds, ed. R. E. Hinchee, A. Leeson, L. Semprini S. K. Ong, pp. 239-47. Boca Raton, FL Lewis Publishers. 

Safe S, Brown KW, Donnelly KC, et al. 1992. Polychlorinated dibenzo-p-dioxins and dibenzofiirans associated with wood-preserving chemical sites Biomontoring with pine needles. Environ Sci Technol 26 394-396. 

Because wood contains several different types of functional groups, chemical reactions with wood-preservative chemicals are a possibility. Depending on the circumstances, such reactions can be... 

Prosecutions fines the annual report identifies 4.7 million as the ongoing cost of environmental remediation programmes and legal costs incurred on the wood preservative chemical spill . Both the CER and the annual report describe this spill in Tennessee in 1994, where civil action has recently resulted in an award of 8.4 million against Hickson (under appeal). In the CER details are also given of an unauthorised discharge of surface water at Pasadena, USA resulting in a 16 000 fine. 

Safe, S., K.W. Brown, K.C. Donnelly, C.S. Anderson, K.V. Markiewicz, M.S. McLachlan, A. Reischi, and O. Hutzinger. 1992. Polychlorinated dibenzo-p-diox-ins and dibenzofurans associated wirth wood-preserving chemical sites biomonitoring with pine needles. Environ. Sci. Technol. 26 394—396. 

Uses Reactive intermediate for phenol-based reactions reactive flame retardant for phenolics, PC, epoxies antifungal agent wood preservative chemical intermediate for polymeric flame retardants Manuf./Distrib. Aldrich http //www.sigma-aldrich.com, AmeriBrom http //www.ameribrom.com, Fluka http //www.sigma-aidrich.com. Great Lakes http //www.greatiakeschem. com, M orre-Tec Ind. http //www.morretec.com Ocean Chems. 

CUNAPSOL is a water borne wood preservative chemical that may be brush or spray applied for surface protection of most woods. Dip soaking or pressure impregnation of CUNAPSOL will result in deeper penetration resulting in longer preservation of treatable species. The water soluble copper in CUNAPSOL reacts with the cellulose of wood. As a result it is not easily lost from the wood by leaching. This unique formulation extends the service life of beautiful wood products by ... 

Approximately 50—55% of the product from a coal-tar refinery is pitch and another 30% is creosote. The remaining 15—20% is the chemical oil, about half of which is naphthalene. Creosote is used as a feedstock for production of carbon black and as a wood preservative. Because of modifications to modem coking processes, tar acids such as phenol and cresyUc acids are contained in coal tar in lower quantity than in the past. To achieve economies of scale, these tar acids are removed from cmde coal tar with a caustic wash and sent to a central processing plant where materials from a number of refiners are combined for recovery. 

In addition to conventional pesticides such as insecticides, herbicides, and fungicides, there are other chemicals classified as pesticides and regulated under FIFRA. These chemicals include wood preservatives, disinfectants (excluding chlorine), and sulfur. In the United States these chemicals have aimual usage of about 500,000 t, which is equal to conventional pesticides. 

Until the end of World War II, coal tar was the main source of these aromatic chemicals. However, the enormously increased demands by the rapidly expanding plastics and synthetic-fiber industries have greatly outstripped the potential supply from coal carbonization. This situation was exacerbated by the cessation of the manufacture in Europe of town gas from coal in the eady 1970s, a process carried out preponderantly in the continuous vertical retorts (CVRs), which has led to production from petroleum. Over 90% of the world production of aromatic chemicals in the 1990s is derived from the petrochemical industry, whereas coal tar is chiefly a source of anticorrosion coatings, wood preservatives, feedstocks for carbon-black manufacture, and binders for road surfacings and electrodes. 

Chromium-containing wood preservatives and their chemical compositions are Hsted ia Table 13 (199). Chromium compounds have a triple function ia wood preservation (200). Most importantiy, after impregnation of the wood the Cr(VI) compounds used ia the formulations react with the wood extractives and the other preservative salts to produce relatively insoluble complexes from which preservative leaches only very slowly. This mechanism has been studied in the laboratory (201—206) and the field (207). Finally, although most of the chromium is reduced to chromium (ITT), there is probably some slight contribution of the chromium (VT) to the preservative value (208). 

Table 13. Chemical Composition and Specifications for Wood Preservatives ...

Important chemicals derived from phenol are salicylic acid acetylsali-cyclic acid (aspirin) 2,4-dichlorophenoxy acetic acid (2,4-D), and 2,4,5-triphenoxy acetic acid (2,4,5-T), which are selective herbicides and pentachlorophenol, a wood preservative ... 

Wood preservatives appear not to affect emission of corrosive vapours from wood, suggesting that the hydrolysis of acetyl polysaccharides is chemical, not biochemical. Some copper-base preservatives can give enough leachable copper ions to cause galvanic corrosion of other metals, notably aluminium and steel. 

Organic carboxylic acids are commonly found in foods, in the adipate process stream, and as pollutants. Fatty acids are the lipophilic portion of glycerides and a major component of the cell membrane. Phenols are widely used in polymers, as wood preservatives, and as disinfectants. Chloro-phenols such as 4-chlorophenol, two isomeric dichlorophenols, 2,4,6-tri-chlorophenol, three isomeric tetrachlorophenols, and pentachlorophenol were separated on a Dowex (The Dow Chemical Co. Midland, MI) 2-X8 anion exchange resin using an acetic acid-methanol gradient.138... 

Environmental factors have been identified as contributing to the development of NHL. Certain occupations such as wood and forestry workers, butchers, exterminators, grain millers, machinists, mechanics, painters, printers, and industrial workers have a higher prevalence of disease. Industrial chemicals such as pesticides, herbicides, organic chemicals (e.g., benzene), solvents, and wood preservatives are also associated with NHL. 

DNAPLs are mainly liquid hydrocarbons such as chlorinated solvents, wood preservatives, coal tar wastes, and pesticides. Table 18.7 lists some common such chemicals.81... 

Copper sulfate can be described as a by-product of copper refining that is obtained by crystallization of the weak liquor. The copper sulfate precipitate formed is centrifuged, dried, screened, and finally packaged in bags and drum. However, it is produced in some chemical industries by reacting copper shot with sulfuric acid, air, and water. It is widely used as an insecticide, additive nutrients (for soils that are deficient in copper), copper electroplating, wood preservation, and in petroleum refining. 

U.S. Environmental Protection Agency (USEPA) Manufacturers to Use New Wood Preservatives, Replacing Most Residential Uses of CCA, http // www.epa.gov/pesticides/factsheets/chemicals/cca transition.htm (verified 7 May 2003), 2002b. 

---