Study on food adulteration and buying practices among households in an urban slum of Tamil Nadu

S S et al | DOI: 10.65188/nurexus.1050

Page 24

Journal of MedVerse Research & Practice

ISSN: 3107-4278

Study on food adulteration and buying practices among households in an

urban slum of Tamil Nadu

Dr. Sangita S

, Dr. Vishnu Kumar K

Postgraduate, Assistant Professor

Department of Community Medicine, Dhanalakshmi Srinivasan Medical College, Preambular

Email: sangitas963@gmail.com

Submission Date: 20.09.2025

Accepted Date: 18.10.2025

Published Date: 31.10.2025

DOI: 10.65188/nurexus.1050

article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits

unrestricted use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Abstract

Background: Food adulteration remains a major public health concern, particularly in low socioeconomic settings

where awareness and regulatory oversight may be limited.

Objective: To assess the awareness and household practices related to food adulteration and to evaluate the presence

of adulterants in commonly consumed food items among housewives residing in an urban slum community.

Methods: A cross-sectional study was conducted among 250 housewives. Information on awareness and purchasing

practices related to food items was collected using a structured questionnaire. Food samples commonly used in

households, including Toor dal, tea, chilli powder, turmeric, salt, and milk, were collected and tested using standard

qualitative methods for common adulterants.

Results: Most respondents were female with lower educational and socioeconomic status. Awareness of food

adulteration was limited, with only 48.4% of respondents reporting prior knowledge. Packaged food items were

preferred by 55 percent, and 70 percent preferred branded products. Laboratory testing detected iodine deficiency in

37 percent of salt samples. Adulteration was also identified in tea powder (6.3 percent), chilli powder (4 percent),

turmeric powder (3.1 percent), milk samples for starch (3.4 percent) and urea (1.1 percent), and Toor dal for metanil

yellow (2 percent).

Conclusion: Awareness of food adulteration was low among participants, and a high proportion of salt samples were

found to be iodine-deficient. Strengthening consumer awareness, increasing community-level screening, and

ensuring strict enforcement of food safety regulations are essential to protect vulnerable populations. Promoting

simple household food testing methods may support early detection and encourage safer purchasing practices.

Keywords: food adulteration, urban slum, iodine deficiency, consumer awareness, food safety, household practices

Introduction

Food is essential for all living organisms, and its quality plays a crucial role in maintaining health. Food

adulteration refers to the deliberate or unintentional alteration of food quality by adding, removing, or

substituting substances to increase profit or due to negligence during food handling. It affects properties

such as colour, taste, appearance, weight, volume, and shelf life. In India, food adulteration may be

intentional or unintentional, and occurs when food fails to meet established standards, compromising its

quality and safety [1]. Adulteration may stem from economic motives or poor handling and storage

practices.

Food adulteration is highly prevalent in both rural and urban slum settings, largely due to low awareness

and inadequate regulatory enforcement. Common examples include adulteration of milk with water, starch,

S S et al | DOI: 10.65188/nurexus.1050

Page 25

and detergents; wheat flour with chalk powder; and spices such as chilli and turmeric with brick powder

and lead chromate. Tea leaves may be mixed with iron filings, while fruits and vegetables are treated with

chemicals like calcium carbide and malachite green to enhance ripening and color. Pulses are sometimes

mixed with Kesari dal, and mustard seeds with argemone seeds, leading to severe health issues. Edible oils

may also contain toxic adulterants, posing major health hazards in these vulnerable populations [2-6].

Consumption of adulterated food results in serious health consequences, ranging from gastrointestinal

disturbances to neurological disorders and cancers. The contamination of mustard oil with argemone oil has

resulted in epidemic dropsy and multiple deaths in India [8]. Synthetic chemical dyes and preservatives

used as adulterants are known carcinogens, emphasizing the need for stringent monitoring and public

awareness [9]. Consumers, particularly from low socioeconomic backgrounds, bear significant health and

financial burdens due to adulterated food, making this issue a major public health and economic concern.

Food adulteration is a global problem, with the World Health Organization reporting that approximately 22

percent of food products worldwide are compromised. In India, the Food Safety and Standards Authority of

India (FSSAI) analysed 177,511 food samples in 2022-23 and found 44,626 non-compliant samples [7].

Recent international recalls of Indian spices due to carcinogenic ethylene oxide contamination highlight

ongoing food safety challenges.

Urban slum residents are especially vulnerable to adulterated food due to poverty, limited education, and

restricted access to safe and packaged food [10]. They often rely on loose, unpackaged items sold by

informal vendors, which increases their exposure to adulteration [11]. Lack of awareness and limited means

to detect adulteration further elevate their risk [12]. Consumer behaviour also influences exposure, as many

low-income households do not check quality labels such as AGMARK or ISI, expiry dates, or packaging

integrity [7,13]. Insufficient knowledge about the Food Safety and Standards Act (FSSA) further

contributes to poor consumer vigilance [7,14].

Awareness regarding food adulteration and simple household detection methods remains low among the

general population, particularly in slum communities [15]. Individuals with higher education are more

likely to read labels, examine packaging, and avoid food of questionable quality, while residents of slums

often overlook such precautions due to limited awareness [16]. Despite food safety regulations, only 13

percent of adulteration cases result in convictions, reflecting major enforcement challenges. Lack of

reliable data, underreporting, and insufficient public knowledge further complicate surveillance and control

efforts [15,16]. In this context, the present study aims to assess the extent of food adulteration, examine

purchasing behaviour among homemakers, and evaluate awareness regarding food adulteration and its

associated sociodemographic factors in urban slums of Tamil Nadu.

Materials & Methods

The study was conducted in Preambular, an urban slum located approximately 1 km from the Urban Health

Training Centre of Dhanalakshmi Srinivasan Medical College and Hospital, Preambular, which falls under

the field practice area of the Department of Community Medicine. The study population comprised

homemakers residing in the selected locality who consented to participate. A cross-sectional study design

was used to assess awareness and practices related to the prevention of food adulteration.

The sample size was calculated as 250 using the formula 4pq/l², based on a 76 percent prevalence of food

adulteration reported in previous studies, with 20 percent relative precision and an additional 10 percent

non-response rate. A sampling frame of 250 households was prepared with support from a local social

worker, and systematic random sampling was applied by selecting every twentieth household. If a selected

S S et al | DOI: 10.65188/nurexus.1050

Page 26

house was locked or lacked an eligible respondent, the next eligible household was included.

After obtaining written informed consent, data were collected using a structured questionnaire covering

sociodemographic details, awareness of food adulteration, and food purchasing practices. Small quantities

of commonly used food items such as milk, toor dal, tea powder, chilli powder, turmeric powder, and salt

were collected from each household based on availability and willingness to provide samples. Samples

were transported in sterile containers to the Public Health Laboratory of the Department of Community

Medicine and tested using a standard food adulteration detection kit by trained postgraduate students.

Results were communicated verbally to each household during the subsequent field visit, along with

education on food adulteration prevention.

Data entry and analysis were performed using SPSS version 21. Descriptive statistics were presented as

frequencies and percentages, and the chi-square test was used to determine associations between food

adulteration awareness and sociodemographic variables. A p-value of less than 0.05 was considered

statistically significant. Ethical approval was obtained from the Institutional Ethics Committee, and

confidentiality and voluntary participation were ensured.

The present study obtained ethical approval from the Institutional Ethics Committee of Dhanalakshmi

Srinivasan Medical College, Perambalur (Ref No: IEC/DSMC-PBL/2023/28461). A detailed Participant

Information Sheet was provided to all participants, and written informed consent was obtained prior to their

participation in the study.

Results

Table 1: Sociodemographic Details (n=250)

Variable

Frequency (n)

Percent (%)

Age

Mean = 36.67; SD = 12.75

Gender

Female

250

100

Education

Illiterate (24.3%)

24.4

Primary (26.1%)

26.0

Higher secondary (38.9%)

38.8

Graduate (10.7%)

10.8

Occupation

Unemployed (52.9%)

132

52.8

Employed (25.7%)

25.6

Unskilled worker (21.3%)

21.2

Poverty line status

APL (40.4%)

101

40.4

BPL (59.6%)

149

59.6

The study included 250 female homemakers with a mean age of 36.67 years (SD 12.75). Nearly one

fourth of the participants were illiterate (24.4 percent), while 26 percent had primary education, 38.8

percent had completed higher secondary education, and 10.8 percent were graduates. More than half of

the women were unemployed (52.8 percent), followed by 25.6 percent who were employed and 21.2

percent working as unskilled laborers. Regarding socioeconomic status, 59.6 percent of the participants

belonged to the below poverty line (BPL) category, whereas 40.4 percent were above the poverty line

S S et al | DOI: 10.65188/nurexus.1050

Page 27

(APL). All respondents were female homemakers residing in the urban slum area.

Table 2: Buying practices of housewives on food items (n=250)

Percent

Type of packaging

Packed

55%

Loose

25%

Both

20%

Frequency of purchase

Daily

Weekly

16%

Monthly

50.0%

Based on need

30%

Preference to branded products

Yes

70%

30%

Among the 250 participants, more than half (55 percent) preferred purchasing packaged food items, while

25 percent purchased loose items and 20 percent used both. Regarding the frequency of purchase, half of

the respondents (50 percent) bought food items every month, followed by 30 percent who purchased based

on need, 16 percent who purchased weekly, and only 4 percent who purchased food items daily. A majority

of the homemakers (70 percent) reported preferring branded products, whereas 30 percent did not prioritize

branded items during food purchases.

Table 3: Awareness of food adulteration (n=250)

Variable

Response

Frequency (n)

Percent (%)

Heard of food adulteration

Yes

121

48.4

129

51.6

Encountered food adulteration in the past month

Yes

8.8

228

91.2

In this study, less than half of the participants had prior awareness of food adulteration, with only 48.4

percent reporting that they had heard about food adulteration, while 51.6 percent did not know of it. When

asked about their personal experience with food adulteration in the preceding month, only 8.8 percent

reported encountering adulterated food items, whereas the vast majority (91.2 percent) did not report any

such experience. This indicates a substantial gap in awareness and perceived exposure to food adulteration

among homemakers in the study population.

Table 4: Adulteration in food products tested by the standard lab testing kit

Food Item

Adulterant

Total of

collected

samples

Total Tested

% Adulterated

Toor Dhal

Metanil Yellow

250

234

2.0

Tea Powder

Artificial colour

250

203

6.3

Chilli Powder

Unknown

250

205

4.0

Turmeric

Powder

Unknown

250

237

3.1

S S et al | DOI: 10.65188/nurexus.1050

Page 28

Salt

Iodine Deficient

250

244

37.0

Milk

Starch

250

3.4

Milk

Urea

250

1.1

In the present study, six commonly used household food items were tested for adulteration. Among the 250

samples collected, the highest proportion of adulteration was observed in salt, with 37 percent of samples

found to be iodine-deficient. Tea powder showed adulteration in 6.3 percent of the samples due to artificial

colouring agents, followed by chilli powder and turmeric powder with 4 percent and 3.1 percent

adulteration, respectively. Toor dal exhibited metanil yellow contamination in 2 percent of samples. Milk

samples demonstrated adulteration in the form of starch in 3.4 percent and urea in 1.1 percent of the 80

milk samples tested. These findings highlight significant adulteration in essential food items, particularly

salt, emphasizing the public health need for awareness, routine surveillance, and preventive strategies in the

community.

Figure 1: Percentage of Adulteration

Discussion

There is a lack of awareness about food adulteration among households in the urban slums of Tamil Nadu.

The present study revealed that participants had encountered food adulteration, and laboratory testing

confirmed adulteration in commonly consumed food items. The most concerning finding was that 37.0% of

salt samples lacked adequate iodine, a deficiency linked to goitre and developmental disorders. This closely

mirrors findings by Tiwari et al. [21], who reported 35.8% non-iodized salt in Madhya Pradesh, indicating

persistent gaps in universal salt iodization. Abidfaheem et al. [22] also identified 10.7% salt adulteration

with insoluble impurities in Karnataka.

Among spices, tea powder showed the highest adulteration (6.3%), followed by chilli powder (4.0%) and

turmeric powder (3.1%). These products are often adulterated with dyes or fillers that pose health risks.

Similar adulteration patterns were reported by Patil et al. [23] and Khapre et al. [20] in rural Wardha. Toor

dhal samples contained metanil yellow in 2.0%, consistent with FSSAI surveillance findings and

observations by Thakur et al. [19], who highlighted both the hazards of such dyes and the importance of

educational interventions in detection.

In milk, 3.4% tested positive for starch and 1.1% for urea, findings consistent with Gupta et al. [8]. While

S S et al | DOI: 10.65188/nurexus.1050

Page 29

starch is added to increase thickness, urea mimics protein content and poses serious renal and

gastrointestinal risks.

The study further revealed that 56.3% of respondents preferred packaged food items, while 15.1%

purchased loose items and 28.7% used both, reflecting increasing consumer awareness regarding hygiene,

labelling, and quality. Monthly purchasing was most common (50.0%), followed by purchasing as needed

(32.7%), weekly (14.0%), and daily (3.3%), suggesting bulk-buying behaviour. Notably, 72.1% favoured

branded products, likely due to perceived better quality control. These findings align with Bhatt et al. [7],

who linked education with preference for packaged goods, and Verma et al. [24], who reported similar

urban consumer trends.

Economic factors also influenced purchasing decisions. Although Gupta et al. [8] reported that lower-

income groups often opt for loose items, many below-poverty-line participants in the present study still

preferred packaged brands, suggesting a positive shift in food safety awareness. However, consistent with

Khapre et al. [20], many homemakers failed to read food labels, highlighting gaps in functional literacy.

Overall, these findings reflect growing but incomplete awareness and underscore the need for targeted

educational interventions.

Only 48.2% of participants were aware of food adulteration, and just 8.5% had encountered adulterated

food at home in the previous month. Awareness was lower among semi-urban and less-educated

participants. Similar awareness levels were reported by Ramesh et al. [25] in Karnataka, whereas Sharma et

al. [17] observed higher awareness in urban Delhi, attributed to better education and media exposure.

Thakur et al. [19] also documented low baseline knowledge among women in Chandigarh, with significant

improvement following educational interventions. Abidfaheem et al. [22] reported only 21.3% good

knowledge in Udupi, reinforcing education as a key determinant, as supported by Gupta et al. [8] and Bhatt

et al. [7].

Food adulteration is more prevalent in urban slums due to poverty, low literacy, and reliance on informal

markets. Similar vulnerabilities were reported by Ramesh et al. [25] in Karnataka and Sharma et al. [17] in

Delhi slums. Thakur et al. [19] further noted poor awareness in low-socioeconomic communities, although

education significantly improved knowledge. Abidfaheem et al. [22] and Gupta et al. [8] confirmed income

and education as strong determinants of food safety practices, while Bhatt et al. [7] and Khapre et al. [20]

emphasized poor label-reading behaviour and limited awareness of certification marks.

Food adulteration testing plays a vital role in household food safety. FSSAI [26] has promoted simple

household-level tests, such as iodine tests for starch in milk and acid tests for metanil yellow in pulses.

Thakur et al. [19] demonstrated improved detection skills following community education, while

Abidfaheem et al. [22] reported similar improvements. However, Sharma et al. [17] noted low utilization of

household testing despite moderate awareness, indicating the need for sustained outreach.

India has strong legal frameworks to combat food adulteration. The Prevention of Food Adulteration Act,

1954 [27] laid the foundation, later replaced by the Food Safety and Standards Act, 2006 [28], which

established the Food Safety and Standards Authority of India (FSSAI). Despite initiatives such as DART

kits and the Eat Right India campaign, Gupta et al. [8] and Sharma et al. [17] reported limited consumer

awareness regarding food labelling and certification, highlighting the need for stronger education and

enforcement.

Conclusion

S S et al | DOI: 10.65188/nurexus.1050

Page 30

This study highlights that the urban slum population, predominantly female, with lower educational levels

and limited economic resources, has very limited awareness of food adulteration. Less than half of the

participants had heard of food adulteration, and only a small proportion reported encountering it in the past

month. Most households preferred packaged and branded food products, purchased either monthly or based

on immediate need. Laboratory testing showed relatively low adulteration levels in most food items;

however, salt adulteration was a major concern, with 37 percent of samples found to be iodine deficient.

Smaller proportions of adulteration were detected in tea, chilli powder, turmeric, milk, and Toor dal. These

findings emphasize the need for consumer awareness programs, regular monitoring of food quality, and

strict enforcement of food safety regulations. Promoting simple household-level food testing practices may

also help protect public health in vulnerable communities.

Conflict of Interest: Nil

Reference

1. Momtaz M, Bubli SY, Khan MS. Mechanisms and Health Aspects of Food Adulteration: A Comprehensive

Review. Foods. 2023 Jan 2;12(1):199. doi: 10.3390/foods12010199. PMID: 36613416; PMCID:

PMC9818512.

2. Food Safety and Standards Authority of India (FSSAI). Manual of Methods of Analysis of Foods. New

Delhi: Ministry of Health and Family Welfare; 2016.

3. Shrivastava SR, Shrivastava PS, Ramasamy J. Public health strategies to combat food adulteration. Indian J

Public Health. 2017;61(4):286–7.

4. Kumar D, Nagi HP, Sharma P, Goyal S. Food adulteration detection: A review. J Food Sci Technol.

2014;51(12):4216–25.

5. Indian Council of Medical Research (ICMR). Adulteration of Common Foods: A Report. New Delhi: ICMR;

2014.

6. World Health Organization (WHO). Toxicological evaluation of certain food additives and contaminants.

Geneva: WHO; 2015.

7. Bhatt SR, Bhatt SM, Singh A. Impact Analysis of Knowledge Practice for Food Safety in Urban Area of

Varanasi. Pak. J. Nutr. 2010;9 (2):186-190.

8. Gupta N, Panchal P. Extent of Awareness and Food Adulteration Detection in Selected Food Items

Purchased by Home Makers. Pak. J. Nutr. 2009;8 (5):660-7.

9. Pririti, Sharma K, Kaushal S, Shubham, Rajput R. Overview of Food Adulteration: Its Definition, Causes,

Impacts, and Detection. J Sci Res Rep. 2024;30(11):801-811. https://doi.org/10.9734/jsrr/2024/v30i112607

10. Agarwal Y, Gupta V, Yadav M, Neelam DK, Devki, Rahi RK. A Review of Food Adulteration and Its

Impact on Human Health. J Coast Life Med. 2023;11(1):1649.

11. FSSAI: Increase surveillance, random sampling of food items to check adulteration, FSSAI tells states. The

Economic Times. 2023 Mar 10.

12. Mohapatra B. Honey Adulteration and Corporate Irresponsibility in India: Visualizing Corporate

Sustainability. Vision. 2025;29(1):1-12. https://doi.org/10.1177/23197145231158448

13. Pathak M. Food Adulteration: Impact on Human Health and Hidden Loopholes in Implementation of the

Laws. Vivekananda J Res. 2023;13(1):32–46. https://doi.org/10.61081/vjr/13v1i104

14. Vijaya Lakshmi D, Prasad KC, Nagasree K, Sirisha Y. Current trends in regulatory actions against

misbranding and adulteration. Int J Allied Med Sci Clin Res. 2023;11(4):420-426.

https://doi.org/10.61096/ijamscr.v11.iss4.2023.420-426

15. Das C. Development Of Impedance and Capacitance based Sensors for the Estimation of Adulterant

Ingredients in Different Bio-Consumables. arXiv. 2024 Jan 3. https://arxiv.org/abs/2401.01729

16. Benadicta YJ, Mano R, Moulishvarran M. Combating Food Adulteration In India: Legal Challenges,

Consumer Awareness, And The Path To Safe Food. Indian J Law Legal Res. 2024 Sep 16.

https://www.ijllr.com/post/combating-food-adulteration-in-india-legal-challenges-consumer-awareness-and-

the-path-to-safe-foo

S S et al | DOI: 10.65188/nurexus.1050

Page 31

17. Sharma M, Vinayak S. A Critical Analysis of Food Adulteration in India. Int J Law Manag Humanit.

2024;7(2):3955-3965. https://doi.org/10.10000/IJLMH.117485

18. Parul, Kaur G. Food Adulteration And Its Detection Using Artificial Intelligence. Educ Adm Theory Pract.

2023;29(4):2576–2583. https://doi.org/10.53555/kuey.v29i4.7236

19. Thakur M, Walia I, Singh A. Impact of health education package on knowledge and practices of women

regarding food adulteration. J Nurs Midwifery Res. 2009; 5(1):1-9.

20. Khapre MP, Mudey A, Sonali Chaudhary et al. Buying Practices and Prevalence of Adulteration in Selected

Food items in a Rural Area of Wardha District: A Cross - Sectional Study. Online J Health Allied Sci. 2011;

10(3): 1-4.

21. Tiwari S, Dubey N, Bansal S. Assessment of iodine content in edible salt at household level in rural Madhya

Pradesh. J Family Med Prim Care. 2022;11(2):824–829.

22. Abidfaheem TK, Nayak BS, Andrade M. Food adulteration and family’s knowledge on food adulteration in

selected village of Udupi Taluk, Karnataka. Nitte Univ J Health Sci. 2013;3(2):33–38. [FOOD.pdf]

23. Patil H, Kulkarni R. Prevalence of food adulteration in selected food items: A rural perspective. Indian J

Public Health Res Dev. 2021;12(1):110–115.

24. Verma S, Yadav R, Singh P. Consumer preferences and buying behavior for packaged food products. J

Retail Mark. 2021;12(3):44–9.

25. Ramesh P, Kumar R, Reddy V. A study on awareness about food adulteration among homemakers in semi-

urban Karnataka. Int J Community Med Public Health. 2020;7(3):1120–4.

26. Food Safety and Standards Authority of India (FSSAI). Detect Adulteration with Rapid Test (DART) Booklet.

New Delhi: FSSAI; 2016.

27. Government of India. The Prevention of Food Adulteration Act, 1954. New Delhi: Ministry of Health and

Family Welfare; 1954.

28. Government of India. The Food Safety and Standards Act, 2006. New Delhi: Ministry of Law and Justice;

2006.