Heavy Metals and Pesticides

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The role of mangroves on the bioaccumulation and citogenotoxic effects of metals and pesticides on the food web of a sub-tropical coastal system

Research Team: 
Chan Shek Kiu (PI) | Karen Arano-Tagulao (co-PI) | Nora Tam (Team Member) | Eduardo Rocha (Team Member) | Patricia Teixeira Cardoso (Consultant). 

Mangrove ecosystems are unique habitats which offer a great variety of goods and services to the ecosystem and to the society. Unfortunately, they have been globally threatened by urbanization and industrialization which have triggered widespread overexploitation of the world’s mangrove forests despite their ecological and economic importance.
 

In South China, namely in Macao, the health and integrity of mangroves are aggravated due to substantial discharge of industrial sewage into the Pearl River Estuary (PRE) from the coastal cities. Among different types of pollutants in the sewage, trace metals are of special concern since alarming levels of cadmium, lead and zinc were annually discharged into the Pearl River, potentially causing far-reaching ramifications on human health and ecosystems.

Besides metals contamination, pollution by pesticides is of great concern because of their ability to cause, in a global scale and years ahead from the present, severe environmental, ecologic and health consequences.
Despite the numerous studies on phytoremediation, little attention has been to the role of mangroves on the bioaccumulation and citogenotoxic effects of metals and organic compounds on the food web and consequently on human health. So, the main objectives of this project are:
 
1) to do a spatial/seasonal characterization of the abiotic parameters as well as contaminants (metals and pesticides), the latter through a time-integrated passive sampling method, in mangrove vegetated versus non-vegetated areas;
2) to do an in situ characterization of the metals and pesticides levels at the biotic compartments along the food web (primary producers, primary consumers and predators) in mangrove vegetated versus non-vegetated areas;
 
3) to evaluate the in situ genotoxic effects and oxidative stress responses to contaminants exposure in vegetated versus non-vegetated areas;
4) to study the bioaccumulation and elimination kinetics and oxidative stress responses in the edible bivalve Geloina erosa to trace metals and pesticides exposure during a field transplant experiment.
 
Through the implementation of this project it is possible to better understand the role of mangroves on the protection of fauna and human health against these pollutants and establish possible management and conservation strategies.
 
Funded by FDCT, reference no. 117/2014/A3. Research Team: Chan Shek Kiu (PI, ISE/USJ), Karen Arano-Tagulao (co-PI, ISE/USJ), Patricia Teixeira (Consultant, CIIMAR, University of Porto), Nora Tam (Team member, City University of Hong Kong), Eduardo Rocha (Team Member, University of Porto)
紅樹林對亞熱帶海岸系統食物鏈金屬的富集和細胞基因毒牲的影響及殺蟲劑的角色
紅樹林是獨特的自然生態系統，為整個生態系統及人類社會提供各種類型的商品及貢獻。然而，城市化及工業化的發展正逐步威脅全球紅樹林生態系統，世界各地過度開採紅樹林，無視其生態及經濟價值。
 
在華南地區，例如澳門，大量從沿海城市排入珠江口的工業污水加劇了對紅樹林健康生長及完整性的威脅。在污水中所含的各種污染物中，微量金屬引人關注，達警戒水平的鎘、鉛、鋅等金屬每年被排放到珠江中，對人類健康及生態系統產生潛在的深遠影響。
除了金屬污染，農藥污染是另一大關注點，該污染今後可能會在全球範圍內造成嚴重的環境、生態及健康後果。儘管目前對植物修復有諸多的研究，但有關紅樹林對於（有毒物質）生物體內積累和食物網中金屬及有機化合物的基因毒性效應及對人類健康的影響還少有人關注，因此，本課題的主要目標是：
 
1）對非生物參數及污染物（金屬及農藥）開展空間/季節性的定性研究，對污染物的定性研究是在紅樹林植被覆蓋地區及非覆蓋地區採用時間積分被動採樣方法；
2）在紅樹林植被覆蓋地區及非覆蓋地區開展食物網（初幾生產者、初幾消費者及掠食者）各級生物中的金屬及農藥水平的實地定性研究；
 
3）在紅樹林植被覆蓋地區及非覆蓋地區實地評估基因毒性效應及對污染物的氧化應激反應；
 
4）在野外移植實驗中研究可食用雙殼類生物紅樹蜆暴露在微量金屬及農藥中體內有毒物質積累、消除動力學及氧化應激反應。本課題的實施可以使我們更好地理解紅樹林在保護動物及人類健康免受污染物威脅中所扮演的角色，並建立相應的管理及保護策略。