Laboratory of Endocrinology and Hormone-dependent Tumors, School of Biochemistry and Biological Sciences, Universidad Nacional del Litoral, Santa Fe, Argentina.
Chemosphere. 2011 Jun;84(3):311-7. doi: 10.1016/j.chemosphere.2011.04.013. Epub 2011 May 4.
Organochlorine compounds (OCCs), like pesticides (OCPs) and polychlorinated biphenyls (PCBs), are persistent lipophilic chemicals classified as endocrine-disruptors. Caiman latirostris inhabits wetlands throughout north-eastern Argentina and may accumulate OCCs. The aims of this study were to determine OCC residues in the eggs of C. latirostris and to correlate OCC burden with clutch size, hatching success and hatchling survival as measures of reproductive performance. Fourteen caiman clutches were harvested from sites with different degrees of anthropogenic intervention on wetlands surrounding Paraná River tributaries. Two to four eggs by clutch were used to quantify OCCs. OCP residues were found in all clutches. The principal contributors to the OCPs burden were the DDT family (range BDL-153.0 ng g(-1) lipid) and oxychlordane (range BDL-34.3 ng g(-1) lipid). PCBs were present in 92.9% of the clutches (range BDL-136.6 ng g(-1) lipid). Both higher concentrations and higher diversity of pesticides, including endosulfan sulfate, were found in the nests harvested close to croplands. A negative correlation was found between clutch size and ∑OCCs (p=0.02, Pearson r=-0.53, r(2)=0.28), mainly due to the ∑OCPs (p=0.04, Pearson r=-0.54, r(2)=0.30). Since egg OCCs concentrations predict maternal burden, present findings suggest that higher OCCs exposure could lead to smaller clutches. Although, other factors like mother age could influence clutch size. Additionally, as caimans are a long-lived and non-migratory species, the maternal OCCs burden reflects the environmental status throughout their home range; thus, caiman eggs could be useful as a biomonitor of local contamination.
有机氯化合物（OCCs），如农药（OCPs）和多氯联苯（PCBs），是持久性亲脂性化学物质，被归类为内分泌干扰物。凯门鳄栖息于阿根廷东北部的湿地，可能会积累 OCCs。本研究的目的是确定凯门鳄卵中的 OCC 残留，并将 OCC 负担与卵的大小、孵化成功率和幼体成活率相关联，作为繁殖性能的衡量标准。从 Paraná 河支流周围湿地受到不同程度人为干预的地点采集了 14 个凯门鳄卵巢。每个卵巢使用 2 到 4 个卵来量化 OCCs。所有卵巢都发现了 OCP 残留。DDT 家族（范围 BDL-153.0ng g(-1) 脂质）和氧化氯丹（范围 BDL-34.3ng g(-1) 脂质）是 OCPs 负担的主要贡献者。92.9%的卵巢中存在 PCBs（范围 BDL-136.6ng g(-1) 脂质）。在靠近农田的巢中发现了更高浓度和更多种类的农药，包括硫丹硫酸盐。卵中 OCCs 的浓度和种类与卵的大小呈负相关（p=0.02，Pearson r=-0.53，r(2)=0.28），主要是由于∑OCPs（p=0.04，Pearson r=-0.54，r(2)=0.30）。由于卵中 OCCs 的浓度可以预测母体的负担，因此目前的研究结果表明，更高的 OCCs 暴露可能会导致卵的数量减少。尽管如此，其他因素，如母亲的年龄，也可能会影响卵的大小。此外，由于凯门鳄是一种长寿且非迁徙的物种，母体的 OCCs 负担反映了它们整个家园范围内的环境状况；因此，凯门鳄卵可以作为当地污染的生物监测物。
