CHAPTER VII

ENVIRONMENTAL RESEARCH

 

Research and development activities play an important role in assessment and control of pollution. The important research activities carried out during the year 2000-2001 in various fields like environmental monitoring, pollution assessment, pollution control, treatability studies, standardisation of analytical techniques, analytical quality control (AQC); continuous monitoring of air and water quality and meteorological studies are summarised below.

7.1 STANDARDIZATION OF METHODOLOGY FOR ANALYSIS OF ADSORBABLE ORGANIC HALOGENS (AOX) IN 
ENVIRONMENTAL SAMPLES

To propose standard procedure for Adsorbable organic halogen (AOX) analysis and to develop the capability for estimation of AOX in different types of environmental samples, the project on standardization of methodology for analysis of AOX in environmental samples had been taken up in during 1998-99 and 1999-2000, within the frame work of project work plan following main activities have been carried out.

Data generated by participating laboratories are compiled and processed for repeatability, reproducibility and spike studies. Under intra-laboratory study, analysis for four standards of 50,100, 200 & 250 mg/l was carried out by each participating laboratory to assess the recovery and repeatability of results by the methodology adopted.

After preliminary period data has been generated satisfactorily by each of the participating laboratory. The continuous check on accuracy was followed during the analysis of synthetic and field samples by analysis of control sample, so that time related deterioration of data could be checked. For this purpose, quality control chart had been established based on the data generated during analysis of one of the standard viz.100 mg/l. The estimate of standard deviation from preliminary period data was used to calculate the warning and action limit of the chart. Control chart based on the preliminary period and control sample data provided by the participating laboratories were plotted. Common practice is used ± 2 S and ± 3 S limits for the warning limit (WL) and control limit (CL) respectively, where S represents standard deviation.

7.2 DEVELOPMENT, STANDARDIZATION AND PREPARATION OF AQC SAMPLES FOR TOTAL COLIFORM AND FAECAL 
COLIFORM PARAMETERS FOR CONDUCTING AQC EXERCISES

CPCB is conducting AQC exercises since 1991 covering 20 physico-chemical parameters. So far 8 full rounds of exercises in 17 slots were conducted. In this endeavour, bacterial parameters like Total Coliform and Faecal Coliform are not yet started which are very much essential from the water quality assessment point of view. The constraints in preparation of bacterial AQC samples are preservation and despatch of samples in ice cold condition. To overcome these problems it was decided to prepare lyphoilized bacterial samples in solid form like the one developed for BODSEED in collaboration with Centre for Biochemical Technology(CBT), CSIR, Delhi.

The main objectives of the proposed project are :

Bacterial samples developed by CBT were tested in CPCB laboratory . Further studies in this project work is in progress.

7.3 DEVELOPMENT OF CERTIFIED REFERENCE MATERIAL (CRM) OF TOXIC METALS USING INDUSTRIAL EFFLUENTS

Trace metals constitute significant health hazard to human beings and occupies an area of particular concern and priority in environmental research. Some of the metals such as Fe, Cu, Zn, Mg, Ca are essential nutrients to aquatic life as well as to human being upto some extent but some other metals are toxic to plants and animals. The need for accurate analytical measurements of metals during environmental monitoring is well recognized and accomplished with use of reference material.. Standard Reference Materials (SRM`s) are well characterized material used to maintain the quality of measurements.

The use of certified reference material (CRM) during routine measurement of trace metals is quite expensive therefore it has become necessary to develop economical and indigenous Certified Reference Material (CRM). Central Pollution Control Board has undertaken project for preparation of Reference Material for toxic metals in industrial effluents under sponsorship of Department of Science & Technology (DST). During first phase of the project (Year 2000-2001). The Certified Reference Material for Nickel, Chromium and Copper were proposed to developed. For preparation of CRMs using electroplating industrial effluent, the samples and standard solutions for the metals Nickel, Chromium and Copper had been distributed to 32 reputed environmental and R&D laboratories in the country for analysis. In order to certify it as Reference Material, the analytical data as obtained from 32 laboratories have been compiled, statistically processed and computed in order to certify its use as reference material and to certify its reference value. During second phase of the project, the stability of the developed CRM's have been thoroughly studied at room temperature in order to assess the stability, degradability (if any) in the solution and consequent changes in CRM due to storage. These samples have been analysed regularly for about an year on monthly frequency. The change in the metal contents, summary of observations on analytical values made on the basis of the results are presented in Table 7.1.

Table 7.1 Stability Test of Developed CRMs and Control Samples stored at Room temperature

S.No.
Month
Certified Reference Material Average Concentration
Control SampleAverage Concentration
Nickel(mg/l)
Cromium(mg/l)
Copper (mg/l)
Nickel(mg/l)
Cromium (mg/l)
Copper(mg/l)
1.
April,2000
4.25
6.50
2.10
2.53
1.45
1.97
2.
May, 2000
4.39
5.16
1.83
2.30
1.43
1.71
3.
June, 2000
4.20
5.06
1.92
2.36
1.49
1.78
4.
July, 2000
4.06
5.18
1.87
2.27
1.45
1.73
5.
August, 2000
4.06
5.25
1.96
2.23
1.43
1.79
6.
September,2000
4.14
5.77
1.92
2.16
1.37
1.76
7.
October, 2000
3.80
7.12
1.85
2.16
1.62
1.72
8.
November, 2000
3.73
7.74
1.81
2.14
1.54
1.72
9.
December, 2000
3.86
7.52
2.06
2.27
1.40
1.89
10.
January, 2001
3.74
6.35
2.12
2.02
1.56
1.94
11.
February, 2001
3.72
6.52
2.06
1.99
1.39
1.93
12.
March, 2001
3.87
5.57
2.02
2.16
1.31
1.84
Minimum Value
3.72
5.06
1.81
1.99
1.31
1.71`
Maximum Value
4.39
7.74
2.12
2.53
1.62
1.97
Average Value
3.99
6.14
1.96
2.22
1.45
1.82
Average Recovery
93.88%
94.62 %
93.33%
87.75%
100%
92.39 %

7.4 DEVELOPMENT OF TOXICITY BASED STANDARD FOR TEXTILE INDUSTRIES

For the development of toxicity based Minimum National Standards (MINAS), a collaborative project had been initiated by CPCB involving five laboratories viz. Gujarat Pollution Control Board, Gandhinagar; National Institute of Occupational Health, Ahmedabad; National Environmental Engineering Research Institute, Nagpur and two laboratories of CPCB located at Kanpur and Delhi. The project work has been undertaken at seven ETPs and one CETP. The selected treatment plants treat effluents generated from synthetic and natural fabric processing units and are located in the states of Gujarat, Uttar Pradesh, Haryana and Rajasthan.

The treated and untreated wastewater samples were jointly collected thrice from the selected ETPs by all the five participating laboratories. The samples thus collected were analyzed for toxicity independently by the laboratories adopting the BIS approved method based on dimensionless toxicity factor (TF). The Toxicity Factor (TF) is the minimum dilution required for the hundred percent survival of test fish during a period of 48 hours.

The analytical results indicates that the range of toxicity factor in the untreated effluents ranged between 4 to 16, whereas in treated effluent its value ranged between 1 to 2. Thus the range of percent toxicity reduction after treatment varied from 75 to 100 percent.

On the basis of results, the Toxicity factor as one (TF=1) recommended as toxicity standard for textile industries, under MINAS, the standard indicates that the treated effluent should not cause any fish mortality, if exposed in the effluents for a period of 48 hrs.

7.5 DEVELOPMENT & STANDARDIZATION OF SPORE TESTING METHODOLOY FOR EFFICIENCY TESTING OF AUTOCLAVES USED FOR HOSPITAL WASTE TREATMENT

The increasing Bio-medical waste generation has become a matter of serious concern for safe disposal of hospital waste in recent years due to increasing health facilities & number of hospitals, nursing homes in metropolitan cities. The Biomedical Waste (Management & Handling) Rules, 1998 notified by Govt. of India, has stipulated rules for proper collection, storage, transportation, treatment and disposal of bio-medical waste. As per Bio-medical Waste Rules, 1998 the hospitals have to install treatment facilities like incinerators, autoclaves, etc. for treatment of bio-medical wastes generated to ensure safe treatment & disposal of infectious hospital waste. These treatment facilities should operate at designed efficiency level.

A project has been undertaken during the years 1999-2000 & 2000-2001 to develop spore-testing methodology for assessment of efficiency of autoclaves used in hospital waste treatment. The major objectives of the project are:

The standardization of spore testing methodology has been undertaken using Bacillus Streothermophilus as biological indicator with a view for its application for efficiency testing of autoclaves used for hospital waste treatment. The standardized methodology has been tested at autoclaves installed at various hospitals within NCT-Delhi for testing their efficiency. The observations & findings of field-testing are presented in Table 7.2.

Table 7.2 Efficiency Testing/Validation of Hospital Autoclaves in
NCT-Delhi by Spore Testing Methodology

S.No.
Autoclave Location
Sampling Month
Location inside Autoclave
Observations
Efficiency Validation
1.
Autoclave I
Dilshad Garden		June, 2000Exposed spore strips in 12
tubes in bags inside autoclave		No turbidity developed
in any tube		Satisfactory
2
Autoclave II
Hari Nagar		September, 2000Exposed spore strips into tubes
in bags inside autoclave		Turbidity developed
in one tube		Partially satisfactory
3.
Autoclave-III
Najafgarh		September, 2000Exposed spore strips in 5 tubes
in bags inside autoclave		No turbidity developed
in any tube		Satisfactory
4.
Autoclave-IV
Sarita Vihar		March, 2001Exposed spore strips in 8 tubes
in bags inside autoclave		No turbidity developed
in any tube		Satisfactory

  Remarks: In case the spore testing strips do not develop turbidity after exposure and incubation, then the efficiency of autoclave is   considered satisfactory (i.e. acceptable sterilization).

The results indicate that the Bio-medical waste treatment autoclaves installed at the hospitals are satisfactory with respect to sterilization of bio-medical waste undertaken at these autoclaves.