recent advances in environmental...
TRANSCRIPT
Recent Advances in Environmental
Analysis
Chemists have all the Fun !
Cool chemists….
1Malaysia…Equally Cool
Organics Lab
ALS Malaysia
7
Recent Advances
• Environmental Forensics
• Rapid Water Toxicity Test
• Microbial Source Tracking
• Oil Spill Analysis
• Metal Speciation
Environmental Forensics
• The application of scientific methods
used to identify the origin and timing
of a contaminant release
• Who, What, When ?
Environmental Forensics
Physical, Chemical, Biological Measurements /
Interpretation
Historical
Info
Fact
witnesses
Tools
• Aerial photography
- Identification of sources and pathways
• Contaminant identification
• Identify ecological stresses and stressors
• Lab Tools and Lab Analysis
- source identification
Environmental Forensics
• Chemistry
• Statistics
• Microbiology
• Hydrogeology
• Toxicology
• Biology
• Environmental Engineering
• Litigation Experience
Lab Tools – Types
• GCs
• ICPs
• Toxicological
• PCR
• Spectrophotometry
Water Toxicity Test
• Rapid Water Toxicity Test - Microtox
• Results within 3 hours
• Widely used in many countries for water
quality assessments
Fish Bioassay
• Traditional method - Acute
Toxicity Test
• Principle:
• The fish are exposed to the
test substance ~ 96 hours.
• Mortalities - recorded 24, 48,
72 & 96 hours – determined
LC50 value
Principle of Operation Patented Bacterial strain
Vibrio fischeri - sensitive
to organic and inorganic
substances.
Respiration includes the
emission of luminescence
from the Lux Gene.
When respiration is inhibited,
the luminescence will
diminish.
Microtox® Toxicity Testing
Non -toxic
sample Toxic sample
Sick or dead bacteria with little or no light
Healthy, bright, luminescent bacteria
Principle of Operation
Measure light intensity
at different
concentrations of
samples
*Result Interpretation
Microtox EC50 Apparent Toxicity Level
0-19 Extremely Toxic
20-39 Very Toxic
40-59 Toxic
60-79 Moderately Toxic
80-99 Slightly Toxic
>100 Nontoxic
*vary from case to case and sample to sample.
Global Acceptance
• United States - U.S. EPA, has adopted Microtox
as a standard test in an ongoing program of
Assessment and Remediation of Contaminated
Sediments.
• Australia - discharge, trade waste and effluent
regulations
• Similarly recognised in Canada, the United
Kingdom, Germany, Sweden and the
Netherlands
Market Segments & Applications
Effluents and Discharges
• Discharge waters
• Industrial Tradewastes
• Mining activities
• Cooling Towers
Leachates
•TCLP prior to disposal
• Landfill leachates
• Slags and Waste for reuse
Waters
•Oil & Gas Exploration
•Oil & Gas Production
•Groundwater monitoring
Soils & Sediments
•Sediments before dredging
•Soils at remediation sites
• Fecal contamination
• Coliform / E. coli
• Countable, not just presence/absence.
Importance of Bacteria as Water Quality Indicators
Sources of Bacterial Pollution • Unmanaged livestock/pet waste • Leaking sewer pipes/storm overflows • Wildlife (mammals and birds) • Malfunctioning septic systems
Microbial Source Tracking
• Traditional methods to monitor fecal
contamination
• Does not identify the Source
• Molecular Biology (PCR) to identify the
Source
• Genus Bacteroides
Microbial Source Tracking
Oil Spill Analysis
• Fingerprinting – GCFID and GCMS
• Biomarkers – GCMS
• Fuel Additives
Figure 2 : Gasoline, Diesel and Motor Oil
GC Chromatograms
GC-Mass Spec
Reliable & Defensible Data
Planning
Sampling
Analysis
Reporting
Sample Preservation
Holding Times
Handling & Transport
QA/QC Systems
Oil Spill Analysis
1) Sampling - at least 1L of water
2) Sample Preparation / Extraction
3) Sample Analysis
4) Quality Control Checks
5) Data Interpretation
6) Conclusion
Arsenic Contamination
• Arsenic – naturally occurring in soil, water and air
• 2 forms of Arsenic – Organic and Inorganic
• Toxic – Inorganic As
• As (III) and As (V) – health hazards
• Arsenic contamination in groundwater is an International Problem.
Major Arsenic Species Measured
arsenite, As(III) arsenate, As(V) arsenobetaine, AsB monomethylarsonic acid, MMA
dimethylarsinic acid, DMA
trimethylarsine oxide, TMAO
Tetramethylarsonium ion, TMAs
arsenocholine, AsCho
arsenosugars: sugar a R = OPO3HCH2CH(OH)CH2OH sugar b R = SO3H sugar c R = OSO3H sugar d R = OH
In blue Species analyze in this work
LC-ICPMS setup (As Speciation)
LC 1260 ICPMS 7700x
Process Flow
ALS - Divisions
