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ABSTRACT

    The paper aimed to understand the water use situation and how the public perceived the current situation of alum-iron water. By using the stratified semi-purposive sampling process, the study explored the perception of people residing in Tri Tôn District, An Giang Province. The applied method involved a structured questionnaire. Perception about sources of pollution was shaped by personal experience. People did not perceive diffused sources of alum-iron pollution that could affect surface water quality. It was found that respondents attributed their risk perception to connect with their direct dependence on the surface water used for their daily needs. The paper suggested behavioural change strategies to focus on social, governing, and technological drivers.

Keywords: iron-alum pollution, Mekong Delta, surface water.

1. INTRODUCTION

    The Mekong Delta with a total area of about 4 million hectares, of which the alum-iron contaminated area occupies an estimated 1.6 million hectares, is distributed mainly in Long Xuyên Quadrangle, Đồng Tháp Mười, Cà Mau Peninsula and Hậu river basin (Võ Tòng Xuân and Matsui, 1998). It was reported that the content of Fe3+ and Al3+ in this area is about 10,78 and 4,28 mg/100g soil, respectively (Hồ Quang Đức et al., 2011). Besides, the content of these metal ions in surface alum-iron water is also relatively high as compared to the National Technical Regulation on drinking water quality - QCVN No. 01:2009/BYT and the National Technical Regulation on domestic water quality - QCVN No. 01-1:2018/BYT (total iron content is about 25 ppm, total aluminium is about 8,5 ppm (Lương Thị Kiều Trinh, 2013). These ions in water would then cause adverse impacts on the life, production, and health of the community.

    Alum-iron soil in An Giang Province with a total area of about 30.136 ha, of which Tri Ton makes up 67%, is distributed more in Tri Tôn, Tinh Biên and part of Châu Phú District which are adjacent to Kiên Giang Province. Therefore, the research team conducted a survey in Vĩnh Phước and Tân Tuyến, communes in order to assess the public perception of the status of alum-iron surface water.

2. MATERIALS AND METHOD

2.1. Site description

    Tri Ton is the largest district in An Giang Province with a natural area of roughly 60.039,74 ha accounting for nearly 17% of the province's area. It has 2 towns and 13 communes. There are 4 main soil groups in Tri Tôn including alluvial soils, acid sulphate soils, peat soils and mountain sandy soils. Since the area of acid sulphate soils in Tri Ton district accounts for 67% of the total acid sulphate soil area of the whole province, the district was chosen for the study. Among the communes, Vinh Phuoc and Tan Tuyen are accounted for 23% of acid sulphate soil group in the district, therefore, they were chosen for the survey. Vinh Phuoc commune has an administrative unit area of about 54,04 km2 with a population density of 33 people/km2. In addition, Tan Tuyen commune has an administrative unit area of approximately 83,35 km2 with a population density of 79 people/km2 (Statistical Office of Tri Tôn District, 2018).

2.2. Data collection and analysis

    A total of 100 questionnaires were distributed evenly to Tân Tuyến and Vĩnh Phước communes. Also, the evaluation form of the current water use status and opinions of the people on the status of alum-contaminated water were implemented by the face-to-face interview method with the help of a self-designed pre-tested semi-structured questionnaire. Prior to the interview, informed consent was obtained from the participants. The households were chosen randomly using a random sampling technique. In this sampling technique, every household in the population has an even chance and likelihood of being selected in the sample. Here the selection of households completely depends on chance or by probability and therefore this sampling technique is sometimes known as a method of chances.

    In 100 questionnaires, 40% of the respondents were male and 60% of the respondents were female. The average age of the respondents in the study area was 48,9 years old, in which the oldest was 96 and the youngest was 25. Regarding occupations (Table 1), the group of people working in agriculture accounted for the majority (45%) of the total number of the respondents. This is a group with high water demand for production needs. Therefore, collecting general information about personal characteristics such as age, gender, and occupation would involve giving opinions on the quality of domestic water, water use demand, and opinion on water use was different. Thus, information can be gathered objectively from individual characteristics (Lê Đức Anh et al., 2018).

 

Table 1. Occupation of the respondents

Occupation

N

Percentage (%)

Farmer

45

48.0

Traders

12

12.0

Employee

18

18.0

Housewife

25

25.0

Total

100

100.0

 

 

3. RESULTS AND DISCUSSION

3.1. Current situation of water exploitation in the study area

    Depending on family economic conditions, water for rural activities in the study area was mainly exploited from natural water sources such as water from rivers, streams, and lakes. Additionally, it was determined that rainwater became the main source of water supply. In order to assess the current situation of water exploitation in rural areas in An Giang Province, the research team conducted a survey of 100 questionnaires (in October 2019) for the subjects of water exploitation. The surveyed area included two communes in Tri Tôn District (Tân Tuyến and Vĩnh Phước communes).

3.1.1. Water sources for daily life and production

    According to the survey results of households in the study area, it was shown that the source of water used for drinking was mainly from the tap water (88%). Among this 88% of the households surveyed, 7% of households used tap water and rainwater in parallel, 11% of households used tap water and river water in parallel. When asked about water for other purposes such as bathing, washing, etc., 84% of households used tap water for this purpose. 16% of households, on the other hand, used other sources of water such as (river water, groundwater, and rainwater). Besides, among 84% of households surveyed, 5% of households used rainwater in parallel with tap water while 20% of households used river water and tap water in parallel. From the above data, it can be seen that most people had access to clean drinking water in rural areas, which, to some extent, can ensure the hygiene and safety of drinking water. However, there were still a significant number of people who were using water directly from rivers, streams, lakes, and rain, etc. to serve their daily needs, including the need for drinking water. These are sources of water that do not meet safety standards, could have a negative impact on the health and activities of the community. At the same time, the study also conducted a survey of water sources used by households for irrigation and production purposes. According to the survey results, 80% of households used water for production and irrigation purposes, including 88% of households exploited river water and the remaining 12% used tap water and river water in parallel to meet production and irrigation needs.

3.1.2. Current status of water uses in the survey area

    It can be seen from the survey results in Figure 1a that the demand of water for drinking in the survey area was in moderate level. On average when the level of water use was at level 1 (less than 100 L/day), this demand accounted for 51%. In contrast, this demand occupied 39% when the level of water use was at level 2 (from 200 L/day to less than 400 L/day).

   At the same time, the survey also conducted an analysis of other domestic water demands such as bathing and washing. As a result, the level of water demand for these purposes was high. To more precise, the proportion of water demand at level 2 made up 39% while that at level 3 accounted for 27% (from 400L to less than 600L/day) (Figure 1b). From the above results, it was shown that the demand and consumption of water in the survey areas were relatively high. It is, therefore, necessary to have a hygienic and safe source of water.

 

Figure 1: Percentage of water demand for (a) drinking and (b) other domestic water demands

 

The analysis results in Table 2 presents a different percentage of respondents’ views on surface water quality. Overall, 38% of people said that the surface water was suitable for drinking and washing, 25% thought that it could only be used for other purposes and 33 % agreed that it could only be used for production purposes.

 

Table 2: Community views on surface water quality

Water quality assessment

Percentage (%)

Used well for drinking, other activities

38

Only used well for other purposes (e.g., bathing, washing, and production)

25

Not good for drinking and daily activities

4

Only used for production

33

 

 

3.2. The status of alum-iron water and the public perception of alum-iron water impacts

    According to the characteristics of sulfate acid soil distribution in An Giang, acid sulfate soils concentrated in areas adjacent to Kiên Giang Province, located in Tri Tôn, Tinh Biên district and part of Châu Phú, with a total area of about 30,136 ha in which Tri Ton accounted for 67%. Therefore, the research team conducted a survey in Vĩnh Phước and Tân Tuyến communes in order to assess the public perception of the status of alum-iron surface water. The survey results showed that in 100 households interviewed, there was 90% of households stating that local surface water sources were contaminated with alum-iron while only 10% said that surface water in the survey area was not contaminated with alum-iron.

    Regarding the awareness of households interviewed about the level of alum-iron contamination of water sources for domestic use (Table 3), for the tap water, 59% of the households believe that the tap water quality was still good and had no sign of alum-iron contamination. On the other hand, the households saying that the tap water had signs of acidity accounted for a high proportion of 38%. Although the level of alum-iron contamination based on people’s opinions was low, this factor still indicated that the current tap water supplied to the households was not good enough.

    For surface water sources around the survey area, the level of alum-iron contamination according to people's opinion is shown by the survey results as follows: high alum-iron level was 26%, alum is low at 64%, and 10% of people believed that surface water was not contaminated with alum-iron. This was consistent with the initial survey of people on alum-iron contamination of surrounding surface water. Because the soil characteristics in the survey area were those of the latent acid sulfate soils, people's judgment on the level of alum-iron contamination was also consistent with the characteristics of this soil group.

 

Table 3. The public perception of the alum-iron contamination level of tap water and surface water in the survey area

Water source

Alum-iron contamination level (%)

High

Low

Non

Tap water

3

38

59

Surface water

26

64

10

 

 

   From the perspective of awareness of the households interviewed about the effects of alum-iron water on their lives, the survey results in Table 4 indicated that 19% of households thought that alum-iron water yellowed clothes and utensils, 39% of households said that it caused itching, drying, and skin burns and 5% of them caused intestinal diseases. Moreover, there was 25% of households judged that alum-iron surface water also caused negative impacts on production activities, but some households believed that alum-iron water did not affect health as well as production, which occupied 22%.

    Most people's perception of negative impacts resulted from alum-iron water sources was mainly from traditional and personal experiences, which accounted for 90%. In addition, 10% of the households interviewed had not complete information about the negative impact of alum-iron water on health and production. In this connection, it is transparent that people's knowledge is based entirely on personal experience and word of mouth without having access to information from the press or mainstream scientific information on the impacts of alum-iron water on the community.

 

Table 4. The public perception of the impacts of alum-iron water on their lives

Impact

N

Percentage (%)

Yellowing clothing and utensils

19

19

Causing itching, drying and skin burns

39

39

Causing intestinal diseases

5

5

Causing a negative impact on production

25

25

Not having influence

22

22

 

 

    When asked about the perception of alum-iron water, most people perceived it by color (64% of people thought that alum-iron water was yellow) and 23% of people said that water had a sour taste. Nevertheless, these sensory criteria come from traditional and personal experiences.

 

Table 5. Sensory criteria of people about alum contaminated water

Sensory criterion

N

Percentage (%)

Fishy smell

6

6

Yellow

64

64

Sour taste

23

23

Turbidity

4

4

Unknown

8

8

 

 

   Although respondents had experience in recognizing alum-iron water as well as the impacts of alum-iron water, when interviewed about alum-iron water treatment, up to 79% of them did not know how to treat alum-iron water, only 16% of them used stove ash to settle alum-iron water, the number of them who knew how to use filter columns or build simple settling tanks accounted for a very low proportion (Table 6). This shows that the respondents had not been propagated or instructed on how to treat alum-iron in water from the locality. Also, access to scientific information was still limited.

 

Table 6. The public knowledge about alum-iron water treatment

The public knowledge

N

Percentage (%)

Not knowing the treatment method

79

79

Treatment by installing filter columns

2

2,0

Treatment by aeration and sand filter

1

1,0

Using lime

2

2,0

Settling by ash

16

16

 

 

4. CONCLUSION

    Through the initial survey results, most rural people had access to supplying water (88% of the households interviewed used the supplying water for drinking purposes, 84% for other purposes). Besides, people also exploited surface water from rivers, lakes, and rain in parallel to serve other drinking and living needs. However, there were still 12% of households using unqualified water sources for drinking and other daily needs and 50% of households interviewed had not implemented water treatment before using.  At the same time, the research team received information from 90% of the households who said that the surface water source was currently contaminated with alum-iron. In addition, alum-iron water was having negative impacts on people's health and life, in which 39% caused itching, drying, and swelling of the skin, 19% yellowed ion clothes and utensils, 5% caused intestinal diseases. Besides, 25% of the alum-iron surface water amount based on people's opinions also caused negative impacts on production activities. People, however, still did not have access to knowledge about the treatment of alum-iron water. Accordingly, the proportion of people who did not know how to treat alum-iron water was very high (79%). Thus, local authorities and officials need to take measures to support the community in accessing scientific information and train people on water treatment before using it for drinking purposes other daily activities with the aim of mitigating negative impacts on the health and life of the community.

REFERENCES

  1. Võ Tòng Xuân and Matsui, S. 1998. Development of farming systems in the Mekong Delta: JIRCAS, CTU, CLRRI, Việt Nam.
  2. Hồ Quang Đức, Nguyễn Văn Đạo, Trương Xuân Cường và Lê Thị Mỹ Hảo, 2011. Evaluation of change in salty saline and acid sulphate soils in Mekong Delta after 30 years of land use (in Vietnamese). Journal of Vietnam Agricultural Science and Technology, Vol. 1 (22)/2011.
  3. Lương Thị Kiều Trinh, 2013. Study on the application of iron oxide catalysts from acid sulfate soil for textile wastewater treatment. Student thesis, An Giang University.
  4. Statistical Office of Tri Tôn District. 2018. Annual Abstract of Statistics 2018. Statistical Office of An Giang Province.
  5. Lê Đức Anh, Hồ Hữu Lộc, Lương Quang Trường, Trần Thành, 2018. Assessment of water use and groundwater quality in District 12 - Hồ Chí Minh City. Journal of Water Resources and Environmental Engineering, Vol. 62 (9/2018), 66 - 71.

 

Nguyễn Trung Thành,1,2,* Nguyễn Hồng Nhật,1,2 Nguyễn Thị Quỳnh Anh,1,2 Phan Phước Toàn,1,2,3 Trần Ngọc Thạch,4 Trần Lê Ba,1,2,3 Tạ Công Khiêm,1,2 Nguyễn Nhật Huy2,3,*

1 An Giang University

2 Vietnam National University

3 Hồ Chí Minh City University of Technology

4 Department of Natural Resources and Environment

(Nguồn: Bài đăng trên Tạp chí Môi trường số Chuyên đề Tiếng Anh I/2020)

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