Laboratori d'Edafologia, Facultat de Farmàcia, Universitat de Barcelona, Avda Joan XXIII s/n, Barcelona, Spain.
Sci Total Environ. 2011 Jun 15;409(14):2707-16. doi: 10.1016/j.scitotenv.2011.03.005. Epub 2011 May 4.
Three chlorophenolic compounds (2-chlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol) were tested to assess their effects on two soils with different properties: a granitic soil (Haplic Arenosol) and a calcareous one (Calcaric Regosol). Different concentrations of the pollutants (ranging from 0.001 to 10,000 mg kg(-1) soil, d.w.) were assayed for their effects on soil microbial activity and composition, using manometric respirometry and PCR-DGGE analysis, respectively. Other ecotoxicity tests such as Lactuca sativa seedling growth in the contaminated soils and algal growth inhibition (Pseudokirschneriella subcapitata) in their water extracts were done. The behaviour of the pollutants in the soils with respect to biodegradability and volatilization was also investigated. In the Haplic Arenosol, volatilization is the main process affecting 2-chlorophenol. Degradation and fixation of this compound in the soil matrix are favored in the Calcaric Regosol. This is the least toxic pollutant assayed. For 2,4,6-trichlorophenol, the soil pH is a critical parameter in the toxicity assays due to the neutral pKa of the compound. It is toxic in the soil microbial activity assay, but some recovery of the biotic processes can be observed, particularly in the Calcaric Regosol. This compound is more toxic in the Haplic Arenosol than in the Calcaric Regosol. Pentachlorophenol is ionized in both soils due to its low pKa, increasing its water solubility. It is highly toxic to the soil microbiota, thus inhibiting respiration, biodegradation and other biotic dissipation processes. Plant and alga tests, were more sensitive than soil microbial tests, except for PCP. The microbial populations tend to show changes at lower concentrations than the microbial activity. Some soil types (abundant in the Mediterranean area), with alkaline pH and fine textures could show higher level of ecotoxicity for ionizable organic pollutants than the soil type recommended by the OECD in ecotoxicity testing.
三种氯酚化合物（2-氯酚、2,4,6-三氯酚和五氯酚）被测试以评估它们对两种具有不同性质的土壤的影响：一种是花岗岩土（Haplic Arenosol），另一种是钙质土（Calcaric Regosol）。不同浓度的污染物（范围从 0.001 到 10,000 mg kg(-1) 土壤，干重）被用于评估它们对土壤微生物活性和组成的影响，分别使用压力呼吸计和 PCR-DGGE 分析。还进行了其他生态毒性测试，例如在受污染的土壤中莴苣种子的生长和藻类生长抑制（Pseudokirschneriella subcapitata）在其水提取物中的生长。还研究了污染物在土壤中的生物降解性和挥发性行为。在花岗岩土中，挥发性是影响 2-氯酚的主要过程。该化合物在土壤基质中的降解和固定在钙质土中得到促进。这是测试的最具毒性的污染物。对于 2,4,6-三氯酚，由于化合物的中性 pKa，土壤 pH 是毒性测定中的关键参数。它在土壤微生物活性测定中是有毒的，但可以观察到生物过程的一些恢复，特别是在钙质土中。与钙质土相比，该化合物在花岗岩土中毒性更大。五氯酚由于其低 pKa 而在两种土壤中均发生电离，从而增加了其水溶性。它对土壤微生物区系高度有毒，从而抑制呼吸、生物降解和其他生物耗散过程。植物和藻类测试比土壤微生物测试更敏感，除了 PCP。微生物种群往往比微生物活性更早地发生变化。一些土壤类型（在地中海地区很丰富），具有碱性 pH 值和细质地，可能比 OECD 推荐的生态毒性测试中的土壤类型对可电离有机污染物表现出更高的生态毒性。
