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Christa Cornelis Johan Bierkens Ingeborg Joris Peter Nielsen Stany Pensaert 《Journal of Soils and Sediments》2006,6(3):156-162
Background, Aim and Scope
The use of organotin compounds as antifouling agents on ships is prohibited at EU level since 1 July 2003. Because of its
persistence, the presence of organotin compounds in harbour sediment will however remain a problem for years. Dumping of dredged
sediment in sea is subject to very strict quality criteria, stimulating the exploration of re-use alternatives, such as re-use
on land.
Within the TBT Clean project (EU LIFE Project 02/ENV/B/341) an assessment framework for re-use of organotin containing treated
sediment on land as secondary granular building material was developed. Three scenarios were considered: free re-use on land,
re-use above groundwater level with cover layer, and re-use under groundwater level (the latter two scenarios are referred
to as restricted re-use). Receptors considered were humans, ecosystem and groundwater. Generic upper concentration limits
and sediment leaching limits were calculated.
Materials and Methods:
Upper concentration limits were calculated with the Vlier-Humaan model. This model allows to calculate soil remediation values
according to the Flemish legal framework. The focus of the methodology is the protection of human health, although a check
for ecotoxicity was included in the project. The soil remediation value for residential land-use was selected within the scenario
for free re-use; for restricted re-use (no direct contact possible), the soil remediation value for industrial land-use was
selected. Leaching values were calculated with an analytical soil and groundwater transport model. The reference scenario
behind the leaching criteria of the European Landfill Directive was modified to fit the project objectives. Default values
for application height and length were used. The point-of-compliance was situated at 20 m distance in the groundwater. Physicochemical
properties were taken from literature; sorption characteristics were taken from literature and were measured on 6 treated
sediment samples during the project. Plant-uptake values were taken from the literature. Toxicological criteria were taken
from EFSA.
Results:
The assessment framework provided an upper limit (SedUL) and an leaching value (SedLV) for each scenario, expressed as mg/kg
dm in the sediment. Criteria were calculated for tributyltin (TBT) and dibutyltin (DBT); too few data were available for monobutyltin
(MBT). The SedUL equalled 0.51 mg TBT/kg dm and 0.07 mg DBT/kg dm for free re-use and 195 mg TBT/kg dm and 205 mg DBT/kg dm
for restricted re-use (two scenarios). For free re-use the SedLV was only limiting for TBT at Kd of < 2000 l/kg in the sediment.
Under re-use above groundwater level with coverage SedLV values ranged from 6.9 – 29 mg TBT/kg dm and from 12 – 33.3 mg DBT/kg
dm (Kd ranging from 100 – 10000 l/kg); under re-use below groundwater level SedLV values ranged from 0.007 – 0.77 mg TBT or
DBT/kg dm (Kd ranging from 100 – 10000 l/kg).
Discussion:
Results are subject to large uncertainties because of variation in input data; the model output is sensitive to variation
in plant uptake (SedUL for free re-use), Koc or Kd (SedUL for restricted re-use, SedLV for re-use with coverage), Henry's
law coefficient (SedUL for restricted re-use); all these parameters show orders of magnitude variation.
Conclusions:
A feasible and consistent framework for evaluation of the re-use of treated organotin containing sediment was developed. However,
the resulting quality criteria are still subject to large uncertainties, due to uncertainties in input data.
Recommendations and Perspectives:
High-quality data on plant uptake and soil sorption of organotin compounds, the influence of soil properties on these processes,
and long-term terrestrial toxicity data are needed to refine the calculations. The quality criteria should be reviewed when
these data become available. 相似文献
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Nelson LL Coelho JC Mietelka K Langohr IM 《Journal of the American Animal Hospital Association》2012,48(2):105-112
Remnants of the pharyngeal apparatus can (rarely) form cysts. This retrospective case series describes clinical and histologic findings of such lesions. Clinical and histology databases were searched for cases of pharyngeal remnants. Eight patients were diagnosed with cysts located subcutaneously in the head and neck, adjacent to the submandibular salivary gland, near the thyroid, and in the mediastinum. Cyst linings included ciliated epithelium, and surgical excision was curative. Knowledge of pharyngeal development is useful for their characterization. Clinicians should consider pharyngeal remnants as differentials for cystic lesions in small animals. 相似文献
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Freya M. Mowat Ingeborg M. Langohr Olenka Bilyk Amy Koterbay Kenneth E. Pierce Simon M. Petersen‐Jones 《Veterinary ophthalmology》2012,15(6):391-397
A 6‐year‐old neutered male domestic short‐haired cat was presented to the Comparative Ophthalmology service at Michigan State University with a 3‐week history of decreased appetite and redness of the left eye. The left forelimb had been removed 15 months previously because of the presence of a subcutaneous fibrosarcoma. In the left globe, a large iridal mass was associated with increased intraocular pressure and retinal detachment. A smaller mass involving the right iris was also present. Imaging revealed a 2‐cm mass in the left caudodorsal lung lobe, and abdominal ultrasound showed multifocal bilateral renal masses. Aspirates of these masses were nondiagnostic. The left globe was removed for palliative reasons, and histopathology showed that fibrosarcoma was infiltrating the iris, choroid, and optic nerve. Despite systemic chemotherapy with doxorubicin, the animal died 4 months after initial presentation. Histopathology confirmed highly angioinvasive metastatic fibrosarcoma also in the right uveal tract, the lungs, and both kidneys. 相似文献
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Roselene Ecco Ingeborg M Langohr Erno Türy Helvécio L Santos Júnior Gabriel C Jacobina 《Journal of veterinary diagnostic investigation》2006,18(5):503-507
A neoplastic mass measuring 25 x 8 x 3 cm was found in the mediastinum of a 10-year-old Holstein cow. The neoplasm was encapsulated, multilobulated, and cystic. Several firm adhesions were present between the neoplasm and the right cranial lung lobe and the ipsilateral side of the pericardial sac. Under microscopic examination, the neoplasm was characterized by solid sheets of spindle epithelial cells (pancytokeratin and high molecular weight cytokeratin positive) subdivided by fibrous trabeculae. Numerous individualized or small aggregates of mature T-cell (CD3 positive) lymphocytes were scattered throughout the neoplastic cell population. Based on the gross, histologic, and immunohistochemical findings, the neoplasm was diagnosed as a mixed thymoma. 相似文献
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A two‐and‐a‐half year‐old male Chinese hamster (Cricetulus griseus) was referred for evaluation of an intraorbital mass involving the right eye. Based on ophthalmic examination and ultrasonography, a diagnosis of intraocular neoplasia was made. Enucleation of the affected eye was performed. The mass was histologically diagnosed as a primary malignant intraocular signet‐ring cell melanoma. No signs of recurrence were detected, and the hamster remained clinically healthy until it died 6 months after surgery. This case report attempts to contribute to the limited body of knowledge available in the literature on primary intraocular neoplasms in hamsters. 相似文献