ASSESSMENT OF THE PHYTOREMEDIATION POTENTIAL OF Spartina alterniflora FOR PETROCHEMICAL INDUSTRY WASTE

Resumo

INTRODUCTION: Persistent organic pollutants (POPs) are a major environmental concern due to their toxicity, persistence, and bioaccumulative capacity in animal and plant organisms. Among them, polycyclic aromatic hydrocarbons (PAHs), which are lipophilic substances, are of special interest because of their persistence and carcinogenic, mutagenic, and teratogenic potential. Given their effects on the environment and human health, there is growing interest in developing alternatives for remediating areas contaminated by oil and its derivatives. On-site technologies reduce transportation costs and, importantly, the risk of spreading contaminants, avoiding secondary pollution. The use of plants as bioindicators and bioaccumulators of pollutants, including hydrocarbons, has shown promise as an environmentally beneficial solution. Spartina alterniflora is native to Brazil and is the main component of the marshes in the Patos Lagoon estuary, RS. It is recognized for its potential as a biomass resource, CO₂ sequester, and pollution remover. OBJECTIVE: This study aims to evaluate the remediation efficiency of soils contaminated with petrochemical waste from the landfarming area of the Southern Petrochemical Complex (Triunfo, RS), using S. alterniflora. MATERIALS AND METHODS: PAH concentrations in the roots, stems, and leaves of S. alterniflora were measured to assess absorption and translocation. PAHs in soil and plants were analyzed using gas chromatography–mass spectrometry (GC-MS), following EPA Method 8270C. RESULTS AND CONCLUSION: Roots showed the highest PAH concentrations in both contaminated and uncontaminated soils. In stems, leaves, and dead leaves, higher concentrations of 2–4 ring PAHs (e.g., phenanthrene, anthracene, pyrene, chrysene) were found. PAH levels in soil decreased in both soil types. High-molecular-weight PAHs, such as benzo(b)fluoranthene and benzo(e)pyrene (5–6 rings), accumulated mainly in roots, with no significant reduction in the soil. The use of S. alterniflora proved effective for removing PAHs, especially those with 2 to 4 rings, through plant uptake and stimulation of microorganisms involved in rhizospheric biodegradation.