Air, Water and Land Pollution
Chapter 1:
Introduction
Copyright © 2010 by DBS
Contents
• Introduction
• Environmental Sampling
• Environmental Analysis
Introduction
• Some examples of scientific studies…
Tellus, Vol. 28, No. 6, pp. 538-551.
Acidification: Finding the ‘Smoking Gun’
Have European lakes Acidified Naturally?
Introduction
Objectives of Study
Parameters of Study
Systematic steps in a monitoring program
Sampling Methods
Analytical Methods
Data: Recording,
Analysis, Presentation
Information Dissemination
Quality control begins
(does not end) here!
Body burdens of lead in ancient people uncontaminated by industrial lead (left); typical
Americans (middle); people with overt clinical lead poisoning (right). Each dot represents
40 µg of lead.
Source: Patterson et al., 1991; adapted from NRC, 1980.
Introduction
• Sampling and analysis – can’t have one without the other
Introduction
•
Objectives of environmental sampling and analysis
– Vary depending on the specific task at hand
e.g.
1. Determining pollutant emissions from smoke stacks, wastewater discharge, etc. in
order to comply with regulatory requirements
2. Measuring background concentrations in order to assess the degree of pollution and
to identify long-term trend
3. To study the fate and transport of contaminants and to evaluate the efficiency of
remediation systems
Rain water
mg L-1
similar
Ca2+/Cl-
River
water
Cl-/SO42-
mg L-1
Sea water
g l-1
Gibbs, 1970
Introduction
Quality of data, and therefore
the overall quality of the study
depends on the sampling,
analysis and interpretation…
Introduction
Since sampling comes first, a
#*$%y sample will lead to
poor data and observations…
Introduction
Also a huge waste of money
since analysis can be pricey…
Introduction
• Analysis – requires reporting of analytical errors (precision,
accuracy, recovery, etc.)
• Must be communication between sampler and analyst to ensure
preservation and storage protocols
Introduction
Importance of Scientifically Reliable and Legally Defensible Data
•
Examples of scientifically defective data:
– Incorrect sampling protocol
– Incorrect analytical protocol
– Lack of good laboratory practice (GLP)
– Falsification of results
Introduction
Importance of Scientifically Reliable and Legally Defensible Data
•
GLP
Introduction
Importance of Scientifically Reliable and Legally Defensible Data
•
•
Legally defensible data is critical in industrial and governmental work
Components include:
– Custody or control
– Documentation
– Traceability (paper trail) – accuracy of standards with certificate of analysis
•
Find examples of falsified environmental data
Introduction
Sampling Error vs. Analytical Error
•
Errors can occur at any time throughout a study
Introduction
Sampling Error vs. Analytical Error
•
Two types of errors:
– Determinate errors (systematic) – errors that can be traced to their source
– Indeterminate errors (random)
•
Random error is dealt with by applying statistics to the data
Introduction
Sampling Error vs. Analytical Error
•
Two types of errors:
– Determinate errors (systematic) – errors that can be traced to their source
– Indeterminate errors (random)
•
Random error is dealt with by applying statistics to the data
Introduction
Sampling Error vs. Analytical Error
•
•
•
•
General consensus is that most error comes from sampling rather than analysis
Direct consequence of the heterogeneity of the environment
Samples must be representative of the features of the parent material being
investigated (Crumbling et al., 2001)
Errors can be quantified and minimized through design and implementation of a
quality program
– Quality control (QC) and quality assurance (QA)
– QC is a system of technical activities to control data quality
– QA is a management system that ensures QC is working as intended
Introduction
Environmental Sampling
Scope of Environmental Sampling
•
Steps in a sample’s life:
– Sample is planned
– Identification of sampling point
– Collection of sample
– Transfer to a laboratory
– Sample is analyzed (destructive/non-destructive)
– Sample expires and is discarded
– Sample is represented as a data point
Sampling
Objective:
Collect a portion of material small
enough in volume to be
transported and large enough for
analysis while still accurately
representing the material being
sampled
Introduction
Environmental Sampling
Where, When, What, How, and How Many
•
Choice of where (spatially) and when (temporally)
to take samples should be based on sound
statistics (judgmental, systematic, random,
stratified, systematic, composite, etc.)
•
No set rules
•
Best sample number is the largest possible!
•
Quantity should not be increased at the expense of
quality…
Lab or Field Analysis?
What are the relative merits of lab and field analyses?
Lab
Pros: analyses performed under optimum conditions, leading to
maximum accuracy, precision will also be maximized
Cons: transport, time delay in getting results, changes to sample during
storage, cost to operate lab
Field
Pros: instantaneous results, no errors due to storage, possible to analyze
in-situ, possible to use continuous monitoring
Cons: conditions may not be optimum, lower precision and accuracy,
Question
Can you guess which of the following water quality determinations
are best made in the lab or in the field?
Nitrate, metals, temperature, pH, dissolved oxygen
Field
Lab
Temperature
Metals
pH
Nitrate
DO
Organics
Introduction
Environmental Analysis
•
Standard analytical methods should be used wherever possible
•
Regulatory agencies require very specific
protocols to be followed
Introduction
Environmental Analysis
Uniqueness of Modern Environmental Analysis
•
•
•
•
•
•
There are numerous environmental chemicals, and the costs for analysis are high
There are numerous samples that require instrument automation
Sample matrices are complex, matrix interferences are variable and not predictable
Chemical concentrations are usually very low, requiring increasingly more
sophisticated instruments to detect ppm, ppb, ppt levels
Some analyses have to be done in-situ (on site) continuously
Analysts need both technical background and knowledge of regulations for regulatory
compliance and enforcement
Introduction
Environmental Analysis
Classical and Modern Analytical Monitoring Techniques
•
e.g. classical titration vs. automated titrator
Introduction
Environmental Analysis
Classical and Modern Analytical Monitoring Techniques
•
Classical methods – include gravimetric and volumetric methods (wet chemical)
•
Modern methods – include spectrometric, electrometric and chromatographic
techniques
Introduction
Environmental Analysis
Classical and Modern Analytical Monitoring Techniques
Introduction
Environmental Analysis
References
•
•
•
•
•
•
•
•
Clesceri, L.S., Greenberg, A.E., and Eaton, A.D., eds. (1998) Standard
Methods for the Examination of Water and Wastewater, 20th Edition.
Published by American Public Health Association, American Water Works
Association and Water Environment Federation.
Cleaves, K.S. and Lesney, M.S. (2005) Capitalizing on Chromatography: LC
and GC have been key to the central science. Enterprise of the Chemical
Sciences, pp.75-82.
Crumbling et al (2001) Managing uncertainty in environmental decisions.
Environmental Science and Technology, Vol. 35, pp. 404A-409A.
Fifield, F.W. and Haines, P.J. (2000) Environmental Analytical Chemistry, 2nd
edition. Blackwell Science, Malden, MA.
Filmore, D. (2005) Seeing Spectroscopy: Instrumental “eyes” give chemistry a
window on the world. Enterprise of the Chemical Sciences, pp. 87-91.
Gibbs (1970) referenced in Reeve, R.N. (2002) Introduction to Environmental
Analysis. Wiley.
Kegley, S.E. and Andrews, J. (1998) The Chemistry of Water. University
Science Books.
Popek, E.P. (2003) Sampling and Analysis of Environmental Chemical
Pollutants: A Complete Guide. Academic Press, San Diego, CA.