Universitas Mulawarman

Universitas Mulawarman
PENELITIAN TOKSIKOLOGI LINGKUNGAN Oleh Drs.Sudrajat,S.U. Dosen pada : 1). FMIPA, 2). Fak.Kedokteran, 3). Fak. Kesmas, 4). Program S-2 Ilmu Lingkungan Universitas Mulawarman Samarinda 2005

( SENYAWA BERBAHAYA BAGI LINGKUNGAN)
PROSES INDUSTRI LIMBAH ( SENYAWA BERBAHAYA BAGI LINGKUNGAN) PENILAIAN EFEK YANG MERUGIKAN TERHADAP BEBERAPA KOMPONEN LINGKUNGAN STUDI TOKSIKOLOGI LINGKUNGAN

PENDEKATAN PENELITIAN
TUJUAN PENELITIAN Melihat perjalanan, perubahan senyawa toksis di lingkungan : dimulai dari sumber; perjalanan di lingkungan; efek paparan terhadap mikroorganisme,hewan, tumbuhan, manusia;sifat-sifat fisika kimia toksikan, sehingga hasilnya dapat dipergunakan antara lain untuk penentuan standar kualitas lingkungan. PENDEKATAN PENELITIAN Studi pengaruh suatu jenis limbah terhadap satu jenis sp Studi pengaruh suatu jenis limbah terhadap komunitas Studi pengaruh limbah terhadap mortalitas Studi pengaruh limbah terhadap efek kronis Studi pengaruh limbah X terhadap kerusakan sistem reproduksi hewan dll

PENDEKATAN PENELITIAN
TES MONOSPESIFIK TES KOMUNITAS EKOSISTEM TERKENDALI PENELITIAN LAPANGAN

INDIKATOR PENCEMARAN LINGKUNGAN

Penentuan toksisitas suatu polutan Identifikasi sumber Jumlah
Beberapa contoh kegiatan penelitian toksikologi lingkungan : Penentuan toksisitas suatu polutan Identifikasi sumber Jumlah Karakteristik fisik-kimia suatu polutan Distribusi dan fate suatu polutan di lingkungan Transformasi polutan secara fisik-kimia- biologi Efek terhadap lingkungan : Identifikasi dan kuantifikasi efek dan respon terhadap lingkungan ( mikroorganisme, hw, tumb,manusia)

ORGANISME UJI untuk studi toksikologi lingkungan
Dipilih berdasarkan tujuan dan target organisme ( apakah hewan/tumbuhan akuatik, organisme darat atau laut Organisme tropik I : Chlorella vulgaris, Selenastrium sp, Scendesmus, kiyambang, dll. Syaratnya organisme tersebut tumbuah dengan cepat dan mudah dikultur Organisme tropik II : Daphnia sp/ Kutu air untuk perairan tawar dan artemia salina untuk perairan laut

Organisme tropik : Konsumen II
Misalnya Ikan mas ( Cyprinus carpio),ikan nila ( Oreochromis niloticus), Mujair ( Tilapia mozambica). Organisme tropik : Konsumen III Burung dara, Puyuh Hewan Tanah : cacing tanah

Penelitian pada perairan :
Dapat dilakukan untuk mengetahui atau mengidentifikasi apakah efluen dan badan air penerima mengandung senyawa toksis dalam konsentrasi yang menyebabkan toksisitas akut atau toksisitas kronis. Penenilitain ini dapat juga untuk menentukan suatu senyawa spesifik yg terdapat dalam efluen, uji ini dapat dilakukan di laboratorium atau secara on site. Data yang diperoleh dapat digunakan untuk memprakirakan potensial toksisitas akuta atau kronis dari efluen dan badan air penerima berdasarkan nilai LC50 dan dengan pengenceran yang sesuai.

HISTOPATOLOGIK ORGAN HEWAN SEBAGAI TOLOK UKUR PENCEMARAN LINGKUNGAN

Tumbuhan air Egeria densa, a potential bioindicator to sediment pollution?
Urban pollution is increasingly becoming a major concern. Whether it is through runoff, leaching of soils, or even through effluent release, pollutants are finding their way into our waterways. There are varying methods for testing for the presence of pollutants. Many are time consuming and costly. One valuable method is through the use of bioindicator species - where the response of plants and animals to pollutants in the environment, are assessed.

Egeria densa was selected as a potential bioindicator species as it is robust, fast growing and readily available. It is a submerged aquatic plant, commonly used in fish tanks and can be highly branched, with branches sprouting from 'double nodes' along the stem. Egeria densa is a very bushy plant ( semak), with dense whorls, containing four leaves per whorl (gelungan). Occasionally 3 to 8 leaves may be present.

Following previous studies, a field collection experiment was conducted in 2004, where samples of the plant were collected from ten different sites, nine of which were in Melbourne and surrounding suburbs, and one on the Victorian/New South Wales Border. The ten sites were of ranging concentrations in heavy metals and nutrients. Plant and sediment samples were collected from each of the sites, and taken back to the laboratory for analysis.

The plants were measured for morphological traits that were found to show trends in previous findings. One of the traits measured in particular was looking at the number of leaves per whorl. From previous experiments, it was determined that the plants from the unpolluted sites on average contained four leaves per whorl, where as those planted in the polluted sediments contained whorls with leaves in varying amounts. The whorls found to contain any number other than four were named 'abnormal whorls'. From this particular study, it was determined that as pollution increases, the number of abnormal whorls increased, similarly to that of the previous studies.

Currently another experiment is underway, involving the spiking of a clean sediment, with varying amounts of a polluted urban sediment, forming a gradual increase in pollution. Plants, originating from a clean site were then added to the sediments. The aim of this experiment is to determine at what concentration we begin to see changes to this morphological trait, and consequently at what concentration the plants are becoming stressed. It is aimed from this study, that it will follow similar trends from previous experiments and hence will allow us to determine whether the plant will be particularly useful as a bioindicator species.

Use of Pollen in Plant Biomonitoring of Air Pollution
Introduction Numerous studies have been devoted to the impact of air pollutants on pollens but in contrast, only few works are available on the use of pollen to evaluate atmospheric pollution (i.e. pollen as bioindicator). Pollen as other plant or animal bioindicators, does not provide information on absolute concentrations of pollutants in the air, however, it indicates, with accuracy, their relative levels.

Bioindicators can give relevant information on pollutants: their identities, their levels and their geographical localisation, and may eventually help us drawing pollution maps. Actually, the methods using plants for biomonitoring of air quality may turn out to be successful, as they are simple, cheap and fast and can supplement the classical physico-chemical methods.

Pollen as Air Pollution Bioindicator
The information on the pollutants is derived from the study of the biological response of pollen to air pollution. As a lot of primary and secondary physiological processes are involved, the physiological responses usable for bioindication could be numerous ranging from molecular level to pollen functioning.

Pollen used as bioindicator gives, from its physiological perturbations, time integrated information on doses of pollutants present in the air. We can say that pollen does not indicate levels of pollutants, but it measures their biological impact. Thereby pollen, as other bioindicators, provides particularly original and interesting information on the potential adverse effects of pollutants on living organisms. This direct assessment of risk by bioindication methods is of greater importance compared to the physicochemical methods.

If in the atmosphere the pollutants have a direct impact on the physiology of pollen, they have also an indirect impact on its ontogenesis via their effects on the producing plants. It may be pointed out that this ontogenesis is also subordinated to the other environmental factors (atmospheric and/or edaphic) acting on the producing plants.

When pollen is used as bioindicator and we want to eliminate these indirect effects, we have to work with pollen coming from plants cultivated in an unpolluted area (greenhouse) and then introduce “in situ” at the beginning of the study (active bioindication), and not with pollen coming from local endemic plants (passive bioindication) with unknown environmental history.

Another easier solution is the “transplant method”
Another easier solution is the “transplant method”. In this case the pollen is first collected from flowers in an unpolluted area, and then exposed in the polluted sites inside narrow-mesh bags. These active bioindication methods have the advantage of being easily standardized at the level of the producing plant and allow to control the pollen characteristics, origin and quality. The “transplant methods” inform with precision how long the pollen has been contaminated.

Pollen as Air Pollution Bioaccumulator
In this case, information on the pollutants is based on the study of their accumulation on the pollen. The accumulated pollutants are quantified after extraction from the pollinic matrix and from physico-chemical analysis.

Due to the rugosity of the micro relief at the surface of pollen (exine), and also due to its lipophilicity, the pollen is a very good accumulator of all types of pollutants: gaseous or particulate on one hand and organic or non-organic on the other hand. This accumulation is mainly dependent on physico-chemical processes at the surface level, and for this reason is not much influenced by the physiological condition of the pollen or of the producing plant. Practically, all the pollutants (pesticides, HAP, heavy metals, fluoride, etc…) can be accumulated on pollen for passive or active bioindication.

Pollen used as bioaccumulator gives information directly linked to pollutant concentrations. The accumulation of pollutants is dependent on the fluctuating characteristics of the air as it is influenced by the dynamic equilibrium between pollen and atmosphere. Indeed, numerous factors tend to continuously eliminate, chemically or mechanically, the pollutants accumulated on the pollen surface: rain, wind, dust, rubbing, etc…

But this information is never instantaneous, as we have to take into account an equilibrium time between atmosphere and pollen which is not very well known.To collect enough biological material, pollen is always directly sampled from the flowers, but in polluted areas, by active or passive bioindication, we never know precisely the contact time between pollutants and pollen. To eliminate this problem, we have to use, as with other bioindicators, the “transplant methods”.

Ozone pollution can cause visible injury to develop on the leaves of sensitive plant species. Typical injury is present on the older leaves as small bronze, brown, or yellow flecks on the upper surface (see photo). In severe cases, the flecks can join to form large lesions covering most of the leaf surface. Ozone injury on clover (Photo: I Fumagalli, Italy)

Heavy metals resulting from mining and industrial activities are pollutants. They can be toxic not only to plants but also to animals and humans through their entry in the food chain through agricultural production. The increasing size of areas polluted by heavy metals makes necessary the use of new strategies to limit the diffusion of this pollution. One of these new strategies is phytoremediation, which consists in using plants to stabilise a polluted soil or to extract metals from such a soil. Phytoremediation could represent an ecologic, alternative and “cheap” option adapted to mild polluted soils. To develop a phytoremediation strategy, one needs plants that are primarily tolerant to metals and, if possible, that are also able to accumulate high concentrations of metals in their tissues. Such plants exist. They are irreplaceable materials to understand the physiological and genetic bases of metal tolerance and hyper accumulation. They unfortunately have reduced biomasses, which limits their potential use for phytoremediation. We need to understand the mechanisms involved in metal tolerance and metal homeostasis and use that information to breed plants that could be used for phytoremediation.

The objective of our group is to unravel mechanisms:
(i) that allow plants to sustain their growth and development in toxic metal environments and (ii) that are involved in the control of metal accumulation in plant aerial tissues. In the past four years, we focused our studies on the metal tolerant and hyper accumulating species Thlaspi caerulescens and Arabidopsis halleri.

Thlaspi caerulescens (left) and Arabidopsis halleri (right) are hyperaccumulators of zinc and cadmium and they are tolerant to these metals. In addition, the Ganges ecotype of Thlaspi caerulescens is tolerant to nickel and hyperaccumulates this metal. The species were photographed in their natural habitats: settling sludge from the Saint Laurent le Minier mine (near Ganges) that contain 12% (w/w) zinc, and the zinc contaminated industrial site of Auby (north of France)

The main achievements of the team have been to shed light on two original mechanisms involved as components of metal tolerance and homeostasis in plants. We showed that the metal tolerance of T. caerulescens and A. halleri occurs, at least in part, at the cellular level. Screening yeast cells expressing cDNA libraries from T. caerulescens and A. halleri for metal tolerance revealed that expression of nicotianamine synthase from T. caerulescens and of type I defensins from A. halleri resulted in nickel and zinc tolerances, respectively. Further analyses showed that (i) nicotianamine plays an important role in nickel tolerance and metal transport in metal hyper accumulating plants; (ii) plant type I defensins have a potential and never mentioned specific role in zinc tolerance.

The Atmosphere Gas Molecular weight No Water Vapor With Water Vapor 2N
28.016 78.09 75.65 2O 32.000 20.94 20.29 O2H 18.016 - 3.12 Ar 39.944 0.93 0.90 2CO 44.010 0.03 Comments These ratios are the same through most of the atmospheric height. Total - is almost 99.99%. Where the pollution goes to ??? Typical atmosphere: N2 - 79%, O2 - 21% and MW

Minor Constituents Gas Molecular Weight Conc., ppm Ne 20.183 0.18 He
4.003 5.2 CH4 16.04 1-2.2 Kr 83.8 1.0 N2O 44.01 NO 30.008 0.002 2NO 46.008 0.004 2H 2.016 0.5 Xe 131.3 0.08 3O 48.000 0.01 Other constituents of the atmosphere include pollen, bacteria, fungi, particles (smoke, sea spray, dust), oxides of carbon, sulfur and nitrogen, and organic gases.

Solid and liquid Particles
Major Groups of Atmospheric Pollutants Main Pollutants Sub Divisions Main Divisions Dust, Smoke, Fog, mists Solid and liquid Particles Particulates 2SO, 3SO Sulfur Oxides Inorganic Gases NO, 2NO, 3HNO Nitrogen Oxides CO, H2S, 2CO, 3O, 3NH Other Compounds 4CH, 6H6C Hydrocarbons Organic Gases HCH:0 Aldehydes PAN Others 3,4-Benzopyrene

Air Pollution Episodes
London Dec 5-9, 1952 Various Parameters High pressure system, Strong night Inversion, fog, poor visibility Meteorological Conditions Flat low terrain Topography Coal home heating Major air pollution sources SO2 levels: ppm; Particulates: mg/m3 Concentration ranges 4000 deaths; bronchitis, emphysema, heart problems Health effects Both sulfur oxides and particles, synergetic effect Mechanism to produce the health effects

RANKING OF AIR POLLUTANTS BY AIR QUALITY GOALS
Basis of Ranking Relative Ranking* Air pollutant Toxicity 0.001 Carcinogens 0.01 Beryllium, mercury 1 Highly toxic metals (Cd, Cr, Pb, Se, V, etc.) 5 Asbestos, silica, silicates Very toxic metals (As, Sb, Cu, Ni, W) Toxicity, corrosion (paint), (odor?) 30 Hydrogen sulfide Toxicity, vegetation damage, electrical conductivity 50 Sulfates, nitrates, fluorides (as salts) Toxicity, vegetation damage Sulfur oxides Toxicity, color, atm. reactions Nitrogen oxides Soiling, toxicity Soot, smoke, carbon black Soiling, visibility 100 Inert particulates corrosion, toxicity Oxidants (ozone, etc.) total Toxicity, atm. Reactions, (odor?) 500 Ammonia 3,500 Carbon monoxide

Ozone Effects On Vegetation
Agricultural crops Yield, Productivity Leaf necrosis Quality

Variables Influencing Plant Response to Ozone
Nutrition, primarily nitrogen Species/genotype Moisture: relative humidity and soil moisture Solar radiation, temperature Day length/photoperiod Regional climatic differences Age of plant, phenological state of development Population/ecosystem interactions

Injury and Damage Injury: All physical or biological responses to pollutants, such as changes in metabolism, reduced photosynthesis, leaf necrosis, premature leaf drop, and chlorosis. Damage: Reduction in the intended use or value of the biological or physical resource; for example, economic production, ecological structure and function, aesthetic value, and biological or genetic diversity that may be altered through the impact of pollutants.

Environmental Effects of Pesticides
Stephen J. Toth, Jr. Wayne G. Buhler Department of Entomology Department of Horticultural Science North Carolina State University North Carolina State University Photograph by Ken Hammond.

What is the Environment?
The “environment” is everything around us natural and manmade; not limited to the outdoors, but including indoor areas in which we live and work. Erwin W. Cole Ken Hammond

How do Pesticides Effect the Environment?
Point-Source Pollution: contamination that comes from a specific, identifiable place (a point) Includes pesticide spills, wash water from cleanup sites, leaks from storage sites, and improper disposal of pesticides and their containers Tim McCabe

How do Pesticides Effect the Environment?
Nonpoint-Source Pollution: contamination that comes from a wide area Includes the drift of pesticides through the air, pesticide run off into waterways, pesticide movement into ground water, etc. Bob Nichols

Environmentally-Sensitive Areas
Sensitive areas include sites or living things that are easily injured by pesticides, including: areas where ground water is near surface or easily accessed through wells, sinkholes, etc. areas near surface waters (oceans, lakes, streams) NCSU Communication Services

Sensitive areas include sites or living things that are easily injured by pesticides, including: areas heavily populated with people (schools, playgrounds, hospitals, nursing homes, etc.) areas populated with livestock and pets Ken Hammond

Sensitive areas include sites or living things that are easily injured by pesticides, including: areas near the habitats of endangered species and other wildlife areas near honey bees areas near food crops and ornamental plants Steve Bambara

Environmental Impact of Pesticides in Air
The atmosphere is an important part of the hydrologic cycle Pesticides enter the atmosphere through drift, wind erosion and evaporation Pesticides can move great distances in the atmosphere Pesticides reach the earth’s surface via dry deposition and precipitation U. S Geological Survey

Long-range movement of long-lived pesticides documented: DDT and other organochlorine pesticides detected in Arctic and Antarctic fish and mammals; used in 1960s and 1970s Toxaphene is still transported into Great Lakes region by winds from the Gulf of Mexico; used on cotton in the South, banned in 1982 USDA/ARS

Pesticides frequently detected in the atmosphere: Organochlorine insecticides (DDT, dieldrin and lindane): widespread use in 1960s and 1970s; resistant to environmental degradation Organophosphate insecticides (chlorpyrifos, diazinon, malathion and methyl parathion): not long-lived in environment; used heavily in the past and at present Triazine herbicides (atrazine): heavily-used herbicides, persistant in environment Acetanilide herbicides (alachlor and metolachlor): used heavily, but not as persistant as triazine herbicides

Number of pesticides detected in air, rain, snow and fog. U. S. Geologic Survey (1995).

Hazards of atmospheric pesticides to humans and environment: Source of exposure to pesticides through inhalation (lungs have surface area equal to tennis court) Source of contamination of surface waters and ground water through dry deposition and precipitation Transport of pesticides from application sites to sensitive areas Accumulation of pesticides in the environment (soil, wildlife, etc.) Gene Alexander

Environmental Impact of Pesticides in Soil
Pesticides can move in the environment via the soil by two methods: erosion and leaching Erosion: soil particles which are transported by wind and water; pesticides attached to soil particles Leaching: downward movement of pesticides in the soil through cracks and pores USDA Photograph

Environmental Impact of Pesticides in Soil Leaching
USDA Photograph Soil normally filters water as it moves downward, removing contaminants such as pesticides Soil and pesticide properties, geography and weather can influence the movement of pesticides (leaching) Pesticides that leach through soils may reach ground water

Environmental Impact of Pesticides in Soil Soil Properties That Affect Leaching
Organic matter: plant and animal material decomposing in the soil; organic matter binds pesticides; the more organic matter in the soil, the less likely pesticides will leach Soil texture: determined by the percentage of sand, silt and clay; the higher percentage of sand, the more likely pesticides will leach USDA Photograph

Environmental Impact of Pesticides in Soil Soil Properties That Affect Leaching
Soil acidity (pH): the acidity of the soil affects chemical properties of pesticides; as the soil pH decreases (becomes more acidic), pesticides bind more to the clay in the soil making the pesticides less likely to reach the ground water Scott Bauer

Environmental Impact of Pesticides in Soil Pesticide Properties That Affect Leaching
Solubility: ability to dissolve in water; the more soluble the pesticide, the more likely it will leach Adsorption: the ability of the pesticide to bind tightly and quickly to organic matter in the soil affects leaching; the greater the ability to bind to organic matter, the less likely pesticides will leach Persistence: how long the pesticide remains in the soil; pesticides degraded primarily by sunlight, soil microbes and chemicals in the soil; the more persistent a pesticide, the more likely it will leach into ground water

Environmental Impact of Pesticides in Soil Effects of Pesticide Application on Leaching
Rate of application: the higher the rate (amount) of pesticide applied, the greater the chance the pesticides will leach Application method: pesticides applied to growing plants can be absorbed by the plants or broken down by sunlight before reaching soil; soil incorporated pesticides are not exposed to sunlight and have greatest chance of leaching into ground water

Environmental Impact of Pesticides in Soil Effects of Geography & Weather on Leaching
Geography: depth from soil surface to ground water (closer ground water is to soil surface, the more pesticide leaches into ground water) Weather: pesticides break down faster in warm, moist soil; therefore, less likely to leach Gene Alexander

Environmental Impact of Pesticides in Ground Water
Ground water is water located beneath the earth’s surface, usually in rock or soil Ground water is the primary source of drinking water for 50% of population, 95% of rural residents in the United States Ron Nichols

At least 143 pesticides and 21 of their transformation products have been found in ground water, from every major chemical class Pesticides commonly found at low levels in agricultural areas (seldom exceed water quality standards) Pesticides also found in non-agricultural setting such as golf courses and residential areas Ken Hammond

Pesticides most frequently detected in ground water: Triazine (atrazine) and acetanilide (alachlor and metolachlor) herbicides: used extensively on corn and soybeans in Midwest Carbamate insecticide aldicarb (Temik): ground water contamination problems, sampled for extensively Bill Tarpenning

Factors strongly associated with pesticide contamination of of ground water are: High pesticide usage in the area High recharge of ground water by precipitation or irrigation High soil permeability Well contamination is greatest in shallow, inadequately sealed wells Tim McCabe

Environmental Impact of Pesticides in Surface Waters
Surface waters include streams, rivers, lakes, reservoirs and oceans Streams and reservoirs supply approximately 50% of the drinking water in United States Ken Hammond

Pesticides enter surface waters through run-off, wastewater discharges, atmospheric deposition (dry and precipitation), spills and ground water Pesticide concentrations in surface waters follow the seasonal patterns of pesticide application and run-off U. S Geological Survey

Low levels of pesticides are widespread in surface waters in the United States Herbicides are detected more frequently than insecticides, due to their greater use Some pesticides exceed water-quality standards during certain seasons, but the annual average concentrations seldom exceed standards Doug Wilson

Pesticides most frequently detected in surface waters: Triazine (atrazine) and acetanilide (alachlor and metolachlor) and 2,4-D herbicides: widely used in agriculture Carbofuran and diazinon were the most frequently detected insecticides in current use Bill Tarpenning

Environmental Impact of Pesticides on Plants
Pesticides can move from the intended target and damage nearby plants, including crops, forests and ornamental plants Phytotoxicity: plant injury resulting from contact with pesticides and/or inert ingredients in pesticide formulations Scott Bauer Bruce Fritz

Environmental Impact of Pesticides on Wildlife
Acute Poisoning: short exposures to some pesticides may kill or sicken wildlife Fish kills caused by pesticide residues carried into waterways by run-off, drift, etc. (e.g., fish kills in Mississippi River resulting from Guthion use in Louisiana) Bird kills caused by birds consuming pesticide-treated vegetation/insects, pesticide granules, bait or treated seed (e.g., birds poisoned by eating granular carbofuran) Ken Hammond

Chronic Poisoning: exposure to non-lethal levels of pesticides over extended periods can cause reproductive effects, etc. Populations of bald eagles and other birds of prey were reduced by the widespread use of organochlorine insecticides (DDT) in 1950s and 1960s These compounds and metabolites caused reproductive effects in birds Reduction in use of organochlorine insecticides in the 1970s and early s resulted in greatly improved reproduction and increasing bird populations Tim McCabe

Secondary Poisoning: occurs when animals consume prey that contain pesticide residues and concentrate the pesticide in their bodies (i.e., bioaccumulation) resulting in their poisoning USDA Photograph Predators become sick after feeding on dead or dying animals poisoned by pesticides Pesticide residues move up the food chain (plants eaten by plant feeding animals which in turn are eaten by predators)

Indirect Effects: adverse effects caused by the modification or elimination of wildlife habitat or food supply Herbicides can reduce food, cover and nesting sites for wildlife Insecticides can reduce insects that serve as food supply for other animals Plant pollination can be effected by reductions in populations of bees and other plant pollinators Ken Hammond

Endangered and Threatened Species of Plants and Animals
Endangered species: “any species which is in danger of extinction throughout all or a significant portion of its range” Threatened species: “any species which is likely to become an endangered species within the foreseeable future” Endangered / threatened species of plants and animals protected by the U. S. EPA under the federal Endangered Species Act Tim McCabe

Harmful Effects of Pesticides on Surfaces
Pesticides can leave a visible deposit on surfaces (i.e., clothes, carpets, walls, etc.) Pesticides can corrode metal surfaces (i.e., paint on automobiles) Pesticides can short-circuit electrical equipment N. C. Pesticide Applicator Training Program

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