Evaluation of Azolla filiculoides potential in pyrene and phenanthrene accumulation and phytoremediation in contaminated waters.

Polycyclic aromatic hydrocarbons (PAHs) are a serious threat to the health of the environment. This study investigated the potential of Azolla filiculoides for the uptake, accumulation, and biodegradation of phenanthrene and pyrene. A- filiculoides plants were treated with 10 and 30 mg L-1 concentrations of phenanthrene and pyrene for the experimental duration of ten days. Phenanthrene and pyrene concentrations were measured using the high-performance liquid chromatography (HPLC) technique. Identification of the intermediate by-products resulting from the biological degradation of PAHs was performed by gas chromatography-mass spectrometry (GC/MS). The quantities of phenanthrene and pyrene in the ten-day treatments with 10 and 30 mg L-1 were 0.007 and 0.011 mg g-1 FW, and 0.048 and 0.079 mg g-1 FW, respectively. The growth parameters in the plants such as fresh weight, dry weight and RFN as well as the content of photosynthetic pigment of the plant decreased significantly compared to the control sample (p < 0.05). Ten compounds were identified from the plant tissue during the decomposition of pyrene and phenanthrene, and none of the PAHs were identified in the aquatic environment. Therefore, the use of A-filiculoides for phytoremediation of water resources contaminated with PAHs is an effective and promising method.

This study estimated the efficiency of Azolla filiculoides phytoremediation in the uptake, accumulation and biodegradation of phenanthrene and pyrene in polluted waters as a total of 100%. High accumulation of pyrene and phenanthrene in the plant tissue decreased plant growth and the number of photosynthetic pigments. GC-MS analysis, identified ten by-products resulting from the degradation of pyrene and phenanthrene in A-filiculoides plant tissue. HPLC analysis showed that there are no substances of PAHs in the water environment.

Pattern of mid-facial fractures in Tehran, Iran.

BACKGROUND/AIM: One of the highest rates of car accidents and related morbidities and mortalities in the world is reported from Iran. Facial structures are usually injured in such accidents. This study is conducted to find the patterns and etiologies of mid-facial fractures in Iran. MATERIAL AND METHODS: During three consecutive years, patients with mid-facial fractures who were referred to a major oral and maxillofacial surgery center were studied for fracture etiologies and fracture locations. RESULTS: Two-hundred and forty-three patients with mid-facial fractures were studied. Male-to-female ratio was 4.5-1. The average age of the patients was 31.7 years, but the 20-29 age group bears the highest rate of mid-facial fractures. Forty-four percent of fractures were related to automobile accidents, and 21% were attributed to motorcycle accidents. Other etiologies are 13.2% for collisions, 10.3% for falls, 6.2% for physical abuse, 2.9% for bicycle events, 1.6% for occupational events, and 0.8% for sport events. Most fractures occurred in zygoma followed by Le Fort and nasal bone fractures. More than half of all patients (80% of automobile and motorcycle accidents) were not either fastening the seat belt or wearing protective helmets. CONCLUSIONS: The main etiology of mid-facial fractures is automobile and motorcycle accidents. Protective measures were not observed in the majority of patients.