# On the use of household expenditure surveys to monitor mismanaged plastic waste from food packaging in low- and middle-income countries

Jim Allan Wright, Simon Damkjaer, Heini Väisänen, Quaranchie

Adama-Tettey, Mawuli Dzodzomenyo, Allan G. Hill, Lorna Grace Okotto,

Joseph Okotto-Okotto, Peter Shaw

► To cite this version:

Jim Allan Wright, Simon Damkjaer, Heini Väisänen, Quaranchie Adama-Tettey, Mawuli Dzodzomenyo, et al.. On the use of household expenditure surveys to monitor mismanaged plastic waste from food packaging in low- and middle-income countries. Environmental Research Letters, 2022, 17 (12), pp.124029. 10.1088/1748-9326/aca623. hal-03889229

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LETTER • OPEN ACCESS

On the use of household expenditure surveys to
monitor mismanaged plastic waste from food
packaging in low- and middle-income countries

To cite this article: Jim Allan Wright et al 2022 *Environ. Res. Lett.* **17** 124029

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LETTER

# On the use of household expenditure surveys to monitor mismanaged plastic waste from food packaging in low- and middle-income countries

Jim Allan Wright<fnref n="1" />,*, Simon Damkjaer<fnref n="2" /> ID, Heini Vaisanen<fnref n="3" /> ID, Quaranchie Adama-Tettey<fnref n="4" />, Mawuli Dzodzomenyo<fnref n="5" /> ID, Allan G Hill<fnref n="6" /> ID, Lorna Grace Okotto<fnref n="7" /> ID, Joseph Okotto-Okotto<fnref n="8" /> ID and Peter Shaw<fnref n="9" /> ID

E-mail: j.a.wright@soton.ac.uk

**Keywords:** domestic waste, food consumption, household expenditure survey, low and middle income countries, mismanaged plastic waste

Supplementary material for this article is available [online](#)

Abstract

**Background:** substantial increases in plastic production have resulted in plastics proliferating of in the environment, with subsequent seabed plastic deposition and ingestion by marine fauna. There is an urgent need to monitor mismanaged plastic waste from household consumption. Household expenditure survey analysis has quantified mismanaged plastic waste generated from household packaged (bottled or bagged) water consumption, but not from consumption of other products.

**Methods:** to evaluate whether household expenditure surveys can quantify mismanaged waste from other widely consumed commodities, we quantify mismanaged plastic waste from the domestic consumption of cooking oil alongside packaged water in urban Greater Accra, Ghana, and all cities nationally in Kenya using two household expenditure surveys. **Results:** household survey-derived estimates indicate packaged water consumption generates considerably more plastic waste than oil packaging in Greater Accra, whereas oil packaging generates more plastic waste than packaged water in urban Kenya. **Conclusion:** by successfully transferring a survey analysis protocol from packaged water to cooking oil, we conclude that there is ample potential for expenditure surveys to be used internationally to quantify mismanaged plastic waste from households. However, uncertainties affecting mismanaged waste estimates need to be accounted for.

1. Introduction

Growing concerns regarding plastic in the
environment [1] are related to mismanaged waste
[2]. This problem stems from the high level of plastic

production, with over 360 million tons produced
globally in 2020 [3]. The resultant proliferation
of plastics has led to widespread impacts [4] and
contamination [5]. Impacts include seabed depos-
ition of plastics, micro-plastic ingestion by and

<footnote n="1">¹ GIS and International Development, School of Geography and Environmental Science, University of Southampton, Building 44, Highfield, Southampton SO17 1BJ, United Kingdom</footnote>

<footnote n="2">² Research Fellow, School of Geography and Environmental Science, University of Southampton, Building 44, Highfield, Southampton SO17 1BJ, United Kingdom</footnote>

<footnote n="3">³ Social Statistics and Demography, University of Southampton, Building 58, Highfield, Southampton SO17 1BJ, United Kingdom</footnote>

<footnote n="4">⁴ Behaviour Change Communication Practitioner, Ministry of Sanitation and Water Resources, Accra, Ghana</footnote>

<footnote n="5">⁵ Ghana School of Public Health, University of Ghana, Legon, Accra, Ghana</footnote>

<footnote n="6">⁶ Population and International Health, Social Statistics and Demography, University of Southampton, Building 44, Highfield, Southampton SO17 1BJ, United Kingdom</footnote>

<footnote n="7">⁷ School of Spatial Planning and Natural Resource Management, Jaramogi Oginga Odinga University of Science and Technology, Bondo (Main) Campus, P O Box 210-40601 Bondo, Kenya</footnote>

<footnote n="8">⁸ Victoria Institute for Research on Environment and Development (VIRED) International, P O Box 6423-40103, off Nairobi Road, Rabuor, Kisumu, Kenya</footnote>

<footnote n="9">⁹ School of Geography and Environmental Science, University of Southampton, Building 44, Highfield, Southampton SO17 1BJ, United Kingdom</footnote>

<footnote>* Author to whom any correspondence should be addressed.</footnote>
entanglement of marine fauna [6], with subsequent
micro-plastic transfer to marine invertebrates [7] and
ultimately species at higher trophic levels including
humans [8].

The uncontrolled release of plastics into the environment relates in part with available waste management systems, which differ markedly between economically developed and developing countries [9]. Open burning of solid waste in low- and middle-income countries (LMICs), for example, releases atmospheric particulates that adversely affect citizens' health [10]. In the absence of waste services, predicted population growth and changing urban consumption patterns in LMICs may exacerbate mismanaged waste disposal.

Extensive reliance on small-scale, ad hoc stud-
ies or country-specific datasets means that ongo-
ing, international monitoring of domestic waste and
its management lacks consistency in study designs
[11]. Since primary fieldwork to monitor domestic
waste generation and disposal is costly, household
expenditure surveys could form a more cost-effective
and internationally standardised means of monitor-
ing mismanaged waste arising from domestic con-
sumption of specific products.

Household expenditure surveys ask a nation-
ally representative sample of households to estim-
ate spending on consumption of goods and services.
They include Household Budget Surveys (HBS),
Income and Expenditure Surveys (IES), and the
World Bank's Living Standards Measurement Sur-
veys (LSMS) [12]. Consumption modules have also
been implemented within some Multiple Indicator
Cluster Surveys [13]. There are now 137 openly
available LSMS surveys for 37 countries (figure 1);
HBS and IES have similar availability. By 2013, 43
of 49 sub-Saharan African countries had conduc-
ted at least one consumption and expenditure survey
[12], although surveys take place only every three
to ten years, so can be outdated. Since many HBS,
IES, and LSMS also record household waste services
or disposal [14], they have potential for character-
ising waste generated from consumption of specific
products, particularly in households lacking waste
services. We previously used household expenditure
surveys in Ghana, Liberia, and Nigeria to character-
ise plastic waste generated through packaged (bagged
or bottled) water consumption among households
lacking waste services [15]. However, it is unclear
if household expenditure surveys could be used to
quantify plastic waste generation from household
consumption of other products and in countries out-
side West Africa.

This study therefore aims to assess (a) whether
household expenditure surveys can be analysed to
quantify plastic waste generation from consumption
of a different product (cooking oil) among house-
holds lacking waste services; (b) how quantities of
plastic waste generated from cooking oil compare

with those from packaged water consumption among
such households.

This study focused on packaged water and cooking oil in Greater Accra Region, Ghana and urban Kenya, thereby exploring household expenditure survey use beyond West Africa. As case study products, we chose cooking oil given its ubiquitous use worldwide, while packaged water consumption is rapidly increasing in many countries (e.g. Laos, Turkey, and Indonesia), forming the main drinking water source for most urban Ghanaian households (58%) in 2019 [16]. Water is sold in bags in Ghana [17], typically in 500 ml plastic sachets [15]. In Kenya, packaged water is mostly bottled [18]. In Ghana and Nigeria, palm oil is generally packaged by vendors or smallholder farmers [19, 20]. Thus, these case studies present contrasting situations for evaluating the potential of household surveys in estimating plastic packaging waste.

2. Method

**2.1. Secondary data sources**

Data pertaining to household consumption patterns
and waste disposal practices are available for both
Ghana [21] and Kenya [22]. The Ghana Living Stand-
ards Survey 7 (GLSS7) is the latest in a series of
nationally representative surveys quantifying house-
hold consumption. In 2016–17, the GLSS7 sampled
1000 enumeration areas (EAs) across Ghana’s ten
regions based on probability-proportional-to-size
sampling. In each EA, 15 households were randomly
selected, resulting in 14 009 sampled households [23].
Respondents reported food and beverage purchases
in the preceding week over six consecutive weeks
and their main means of solid waste disposal. Only
the urban Greater Accra region was evaluated in
the present study, the Ghanaian region where sachet
water consumption is concentrated [15]. In Kenya,
given the more even regional distribution of pack-
aged water consumption, we analysed data for all
cities.

The Kenya Integrated Household Budget Survey (KIHBS) 2015–16 is also a nationally representative cross-sectional household survey. Its clustered sampling design included 24 000 households in Kenya’s 47 counties [24] chosen from 2400 randomly-sampled clusters. In each cluster, 16 households were randomly selected, of which ten were sub-sampled to participate in the main KIHBS. The survey response rate was 91%. The questionnaires addressed sociodemographic characteristics, wealth, economic standing, and consumption expenditure. Adult household respondents reported spending on itemised services and goods, including cooking oil and packaged water, in the seven days before interview. Householders also completed diaries recording their purchases and expenditures.
<figure><img src="image_4.png" /><figcaption>Figure 1. The global distribution of living standards measurement surveys with available micro-data per country, September 2021.</figcaption></figure>

## 2.2. Field data collection

For water sachets in Greater Accra, each 500 ml plastic sleeve was estimated to weigh 1.7 g of high- or low-density polyethylene (HDPE/LDPE) [15]. For other packaging units, 97 and 16 samples of water and oil packaging were collected from markets and kiosks in Kisumu (Kenya) and Greater Accra (Ghana) respectively, from July to September 2021 (Online Resource 1). The empty containers were cleaned and weighed, and the lids and labels were removed.

## 2.3. Data analysis

For both cooking oil and packaged water, purchases were used to infer packaging by classifying the measurement units into four groups:

(a) Specific containers: in Ghana, these include manufacturers' sachets for packaging oil and water, reused branded water bottles, and plastic bags hand-tied by vendors.

(b) Measurement and packaging by vendors (e.g. tins, heaps, beer bottles, branded bottles).

(c) Standard units (e.g. litres or gallons)

(d) Unspecified units (e.g. ‘single’; ‘piece’).

For each product, the mean packaging inefficiency (weight of plastic packaging per unit volume of product) was calculated to convert the consumption data to plastic waste quantities. Published data on cooking oil and water packaging volumes and weights were also obtained for comparison. Search terms relating to the two products ('oil' or 'water'), containers (e.g. 'bottle', 'sachet', 'container') and weight were combined and searches made using Web of Science, Google Scholar and Google. Promotional statistics and data presented without a stated methodology were excluded.

High, medium, and low plastic use scenarios were generated to convert quantities purchased to amounts of packaging), reflecting the uncertainty associated with the survey measurement units. Since most water purchases in Greater Accra were recorded in standard units (sachets or bags of 30 sachets), the associated low, medium, and high scenarios were almost identical. In Kenya, where measurement units for water purchases were mostly in litres, we generated high (0.5 l bottles), medium (1.0 l bottles), and low (1.5 l bottles) waste scenario estimates. In Greater Accra, oil purchases mostly comprised vendor-measured units, so we assumed the widespread use of sachets or hand-tied bags for low and medium scenarios and plastic bottle use for a high waste scenario. In Kisumu, our fieldwork showed that oil was mostly sold in plastic jerrycans. Therefore, in Kenya, our three scenarios assumed: all oil sold in small 1 l jerrycans (high waste); all oil sold in the largest possible jerrycan (medium waste), and half of the oil sold in the largest possible jerrycan and half sold in the largest possible plastic bottle (low waste).

In Ghana, where each household was visited six times, we also used logistic regression to test for significant differences in the reporting of water or oil purchases per survey visit, using regression coefficients to adjust estimates where required. In Kenya, where the KIHBS recorded the retail outlet for each purchase, we also cross-tabulated purchases against retail outlet. Finally, we estimated the annual weight of plastics generated through oil or packaged water consumption according to the main household waste disposal method, differentiating waste collected via service providers from other forms of disposal. Analyses of plastics by waste disposal method accounted for the GLSS7's multi-stage cluster design via the *svy* commands in Stata [25] to generate nationally
representative estimates with 95% confidence inter-
vals reflecting sampling error. Where multiple pack-
aging assumption scenarios were used, the estim-
ate from the medium waste scenario was presented
alongside the widest confidence intervals from any of
the three scenarios used. Finally, to explore the eco-
nomic drivers of lightweight packaging, we examined
the price of 500 ml water sachets versus bottles in
Greater Accra Region via regression analysis.

**3. Results**

3.1. Quantification of plastic waste generation using household expenditure survey data concerning cooking oil and packaged water consumption

Overall, 5% of urban households reported buying packaged water in Kenya during the seven days before interview and 57% reported buying vegetable oil. In Greater Accra, households reported purchasing water sachets in 71% of the weekly survey visits. Logistic regression indicated no significant differences in water purchase reporting by GLSS7 survey round, but respondent fatigue was evident in reported oil purchases following the first visit (odds ratio = 1.14; *p* = 0.03), so reported purchases from subsequent visits were adjusted upwards by 1.09. Oil purchases were more prevalent in urban Kenya, and packaged water purchases were more prevalent in Greater Accra.

In Greater Accra, most water purchases were recorded as individual 500 ml sachets or sachet bags (30 × 500 ml sachets) (figure 2(a)). In Kenya, water purchases were typically expressed in metric units (figure 2(b)). After controlling for the discounting of bulk purchases, regression analysis of packaged water prices indicated that bottled water sold for significantly more than sachet water in Greater Accra Region (GHS1.96 or $0.46 versus GHS0.36 or $0.08, *p* < 0.001).

A wide variety of cooking oil measurement units is apparent in Greater Accra, particularly for vendor-measured units of palm oil (figure 3(a)). Oil is also packaged by manufacturers in sachets rather than in bottles. Some units signify container reuse, such as the use of beer, Fanta (soft drink), or Voltic (water) bottles. Similarly, *olonkas* (American tins) indicate that vendors reuse containers for measuring. In contrast, in Kenya, measurement units for oils were largely metric, although some vendor-measured units such as *gorogoros* (tins for measuring out quantities, cf. *Ghanaian olonkas*) were evident. In the KIHBS (figure 3(b)), vegetable oil purchased from supermarkets was measured in litres in 83% of reported cases, while vendor-measured units were more common in open markets and kiosks.

In terms of container inefficiency, polyethylene
terephthalate (PET) bottles (without lids) used for
water packaging in Greater Accra and Kenya were

broadly comparable with published estimates for
other LMICs (figure 4; Online Resource 1). Only
one set of measurements for oil containers (from
Brazil) was identified from literature, precluding sim-
ilar comparisons for oil containers. Smaller-capacity
containers were generally less efficient than larger
containers. The most efficient containers were sachets
and hand-tied bags, which are used extensively in
Ghana for both oils and water. In Kisumu, the jerry-
cans widely used for oil were less efficient than bottles
(figure 4(b)).

3.2. Plastic waste generation from cooking oil and packaged water consumption

Most plastic waste from sachets in Greater Accra is generated in households that have a formal waste collection system in place, so relatively small proportions are dumped indiscriminately or burned (figure 5(a)). Unlike the GLSS7, the KIHBS records the waste collector type, thereby highlighting the contribution of private companies and informal waste collectors (figure 5(b)).

Consumption of palm or vegetable oils in urban Greater Accra mostly takes place within households with waste collection services (figure 6(a)). The confidence intervals for plastic waste generated are wider than those for packaged water, reflecting the uncertainty in interpreting measurement units (figure 5(a)). In Greater Accra, the total amount of plastics generated from oil consumption is much lower than that of packaged water, as is the number of reported oil purchases (figure 3). In Kenya, private collectors handle more waste from vegetable oil than other collectors do (figure 6(b)). Among Kenyan households that lack waste collection services, plastic waste from oil consumption exceeds that from packaged water consumption.

**4. Discussion**

4.1. Plastic waste insights from household expenditure surveys in Ghana and Kenya

Our household survey analysis provides insights into domestic generation of mismanaged plastic waste. The analysis shows that plastic waste from sachet water consumption (figure 5(a)) far exceeds that from oil (figure 6(a)) in Greater Accra, whereas in urban Kenya, the opposite occurs (figures 5(b) and 6(b)). Although plastic sachets weigh little, sachet water is among the most frequently purchased items recorded in the GLSS7. As noted in the USA [26], the ability to assess the contribution of different food products to mismanaged plastic waste could provide evidence to target regulatory policy concerning food packaging and suitable waste management facilities at specific products of concern. The household survey analysis also quantifies the importance of Kenya's private providers, either working informally or contracted via public-private partnerships [27]. In Kenya, where
<figure><img src="image_5.png" /><figcaption>(a)</figcaption></figure>

<figure><img src="image_6.png" /><figcaption>(b)</figcaption></figure>

**Figure 2.** Measurement units for water transactions per week reported by (a) 1,253 households in urban Greater Accra Region, Ghana, totalled over six weekly visits in 2016–2017; (b) 956 households in Kenya totalled over one week in 2015–16 (x-axis codes are 1: specific container; 2: units for vendor-measured purchases; 3. Imperial/standard unit; 4: unspecified units).

the KIHBS differentiated service providers by sector, private providers collected more oil and water packaging waste than local governments or community associations (figures 5 and 6).

Non-standard measurement units highlight the widespread practice of vendors packaging goods via reused containers. In both urban Kenya and Greater Accra, containers were widely reused in markets
<figure><img src="image_7.png" /></figure>

to measure product quantities and, in some cases,
reused as packaging. Vendors’ resale of smaller, more
affordable quantities of food has been described as
the ‘Kadogo economy’ in Kenya, meaning ‘tiny’ in
Kiswahili [28]. Vendors used margarine tubs or tins
(Gorogoros in Kenya or Olonkas in Ghana) to measure

out commodities for sale, reflecting reported con-
tainer reuse by vendors elsewhere in West Africa [29].
Similarly, soda, beer, and water bottles were some-
times reused to sell vegetables or palm oil (figure 3).
However, systematic recording of container reuse
would likely require ancillary fieldwork. Some widely
<figure><img src="image_8.png" /><figcaption>**Figure 4.** Container inefficiency (grams of plastic per litre of capacity) versus container capacity based on literature review and fieldwork in Greater Accra, Ghana and Kisumu, Kenya, for (a) packaged water and (b) cooking oils.</figcaption></figure>

used non-standard packaging units (e.g. hand-tied bags) were not pre-coded into the GLSS7 survey questionnaire, but could be systematically recorded in future surveys.

Widespread use of lightweight plastic sachet packaging for both oils and vended water is evident in Greater Accra, whereby savings on packaging materials reduce costs to consumers. Although Ghana's sachet water industry has previously been well documented [30], the use of sachets as a lightweight alternative to PET bottles for other products, such

as oils, has not. In the USA, premium bottled water brands have higher packaging inefficiency than budget brands [26, 31]. Packaging inefficiency for bottled water from Mexico and India is similar to that of mid-range US brands [31]. The present study suggests that higher-volume purchases in LMICs entail less packaging per litre than smaller purchases (figure 4). The GLSS7 data suggest that food or beverage products manufactured for LMIC markets sometimes use less packaging than their high-income country equivalents. However, the substitution of
<figure><img src="image_9.png" /></figure>

PET bottles with sachets inhibits their reuse potential. Sachet sleeves, thin films of HDPE or LDPE, are recycled to some extent in Greater Accra and collected by waste pickers [32], but not reused. In contrast,

the reuse of PET bottles permits greater value to be gained from the materials and energy used for their production [33] in alignment with waste hierarchy aims and principles [34].
<figure><img src="image_10.png" /></figure>

For urban water delivery, a three-axis framework has been proposed that characterises its quantity, availability, and delivery [35]. Given the widespread use of packaged water in some LMIC cities, our approach could enable the addition of mismanaged

plastic waste from packaged water as a fourth axis. Successive household surveys also provide opportunities to monitor changes in goods consumed by households lacking waste services in different years within a given country.
## 4.2. Implications for using household expenditure surveys to quantify mismanaged waste from domestic consumption

In applying an analysis protocol developed for packaged water to cooking oil, we also identify some generic issues affecting plastic waste quantification via household expenditure surveys. A typical survey may use standard (e.g. litres) or non-standard units (e.g. bunches) to record food quantities consumed [36]. The quantification of domestic waste associated with packaging requires a conversion table to translate non-standard quantities of specific products into quantities and resin types of plastic waste. Such tables currently do not exist; thus, primary fieldwork is required to quantify the weights of different packaging types associated with commonly consumed foods. However, a multi-country study [37] found that food metrics could be constructed for only 53% of recent household surveys because of the difficulties in constructing conversion tables for non-standard units. Our case study suggests that packaged water is sold in standardised units (figure 2), whereas the units for oils are highly variable (figure 3). Where present, such heterogeneous measurement units pose challenges for the analysis of food and beverage packaging.

Some generic LSMS data quality issues impact their use in domestic waste quantification. For example, 'prestige errors' may lead to over-reporting of socially desirable commodities [38]. Many LSMS use a weekly recall period for food consumption questions administered over multiple, repeated household visits. Respondent fatigue has been noted in some household surveys with repeated visits [39] and was apparent in household reporting of oil purchases in the GLSS7. Reported estimates may also be subject to both 'telescoping', whereby events before the recall period are reported within it, and 'memory decay', whereby consumption details are progressively forgotten as the recall period lengthens [40].

The most widely used recall period in the LSMS is a week [37], which makes it challenging to differentiate between products purchased at different frequencies. Less frequent bulk purchases often entail additional secondary packaging [41], whereas packaging efficiency is generally greater for bulk items (figure 4). However, estimating waste from food consumption as opposed to waste disposal events may be preferable. While many foods are frequently purchased, some waste disposal events may occur less frequently as households accumulate waste before disposal [42].

The commodity codes used in LSMS also likely impact the quantification of packaging associated with domestic waste streams. There is international variation in the number and nature of codes used [37], which reflects the local context and the survey's primary purpose [40]. Commodity code systems are often harmonised to reflect the purpose of

consumption [14]. However, products with similar purposes may be packaged differently. For example, water sold in bottles uses more plastic per unit product than sachet water and generates PET rather than HDPE plastics [15], both may be recorded under a single packaged water commodity code. While the consumption of food away from home (FAFH) is growing in LMICs [40] and many surveys include commodity codes for FAFH foods, few explicitly capture meals or snacks consumed outside the home [43]. Waste disposal facilities for FAFH will also not be captured by LSMS, preventing mismanaged waste quantification for FAFH via surveys.

There are also challenges in measuring domestic waste disposal through household surveys. While LMIC households in cities such as Lusaka, Bulawayo, and Mombasa reportedly separate waste for burning, recycling, or reuse [44], recycling rates are generally low; for example, only an estimated 6% of domestic waste is recycled in Lusaka [44]. Markets for the recycling or reuse of plastic waste vary by product and plastic type. For example, there is extensive informal reuse of water PET bottles in urban Senegal but no reuse of plastics from sachet water [29]. However, in most LSMS, only the main method of waste disposal is typically recorded. Without specific questions on waste separation and secondary waste disposal methods, household surveys may inaccurately estimate mismanaged waste. Furthermore, while surveys such as the KIHBS and GLSS7 identify collected waste, they do not record whether it is safely contained following collection, so overall waste mismanagement may be underestimated.

Household consumption surveys also lack georeferencing. Although Demographic and Health Surveys are released with GPS coordinates for household clusters [45], they lack consumption modules [12]. Conversely, LSMS surveys measure consumption, but their lack of detailed spatial referencing restricts spatial analysis to the provincial level. Studies modelling the onwards environmental fate of plastics typically use river catchments as spatial units [1], and the lack of detailed LSMS georeferencing inhibits the potential integration of derived mismanaged waste estimates with environmental transport models.

## 4.3. Future approaches to quantifying mismanaged domestic waste via household surveys

Several potential approaches could be used to characterise mismanaged domestic waste via household surveys. First, future analyses could focus on a limited number of case study products sold in standardised packaging of particular concern for national waste management. In the USA, such analyses have identified specific products for which packaging can be reduced [26]. In Liberia, Nigeria, and Ghana, for example, water sachets are typically sold in standardised quantities (individual 500 ml plastic sleeves or 15 l bags of 30 sachets), which facilitates the
quantification of plastic waste generated and cross-
tabulation with waste service type(s) [15]. A second
approach would be to classify commodities into
groups based on their packaging, perhaps in conjunc-
tion with data on the retail channels through which
they are sold (where available). Analogous to the
World Food Programme's Food Consumption Score
[12], commodities can be grouped by likely packaging
type (e.g. composites, LDPE, HDPE, PET, card/pa-
per, and glass). However, this would require an expert
understanding of the commodity packaging.

A third approach records both packaging and waste management facilities through a community or market survey module, similar to those used in household surveys for recording prices or neighbourhood facilities. Market survey observations are sometimes used to convert non-standard units in food consumption modules into metric units [46]. However, this approach would increase implementation costs and present challenges in identifying retail outlets used by the sampled households. Although community and price modules are typically implemented within the EAs selected for an LSMS, these small areas do not generally encompass the services or larger retail outlets used by these households [47].

Minor adaptations to existing household survey
designs could enhance their use in quantifying mis-
managed plastic waste and thereby inform initiatives
to better manage the resources and materials con-
sumed in plastic packaging production. Because most
surveys only record the main mode of waste dis-
posal, an additional question pertaining to product-
specific waste separation would be valuable. Simil-
arly, more response categories for waste service oper-
ators would enable a fuller quantification of their
benefits (such as the separate categories for local gov-
ernment, community association, and private waste
operators in the KIHBS). Given that the measure-
ment units and packaging varied for oil purchases
by retail outlet in Kenya, recording the market chan-
nels for purchases has merit. A review of survey
codes for non-standard measurement units could aid
in the understanding of waste. In the GLSS7, for
example, there was no predefined code for hand-tied
plastic bags, despite their widespread use for selling
palm oil. Proposed commodity codes could be also
reviewed against heterogeneity of packaging. In the
GLSS7, for example, there are separate commodity
codes for bottled and sachet water purchases that
facilitate plastic waste quantification. In other coun-
tries, even when bagged water is sold, there is often
only a single commodity code for recording packaged
water.

Finally, estimates of collected and mismanaged
waste from household surveys need to be evalu-
ated through triangulation with other data sources;
retail sector records on product sales and regulator
records on waste composition [26], combined with
bespoke household surveys to assess waste generation

[48] are of merit, although these are scarce in
LMICs.

5. Conclusions

There is considerable potential to exploit existing
international household consumption surveys for the
quantification of domestic waste. This case study of
cooking oils and packaged water in Greater Accra,
Ghana, and Kenya demonstrates quantification of
domestic mismanaged plastic waste, container reuse
and the use of sachets as lightweight, inexpensive
packaging. It also highlights the contributions of dif-
ferent service providers in Kenya to domestic waste
collection. There are nonetheless challenges arising
from variations in survey implementation and con-
tent. Some of these challenges could be addressed
through the adaptation of household survey proto-
cols, for example, by aligning measurement units on
questionnaires with widely used forms of packaging.
There is also a need for complementary fieldwork,
particularly for market surveillance of packaging,
to enable more robust quantification of misman-
aged plastic waste. Data enabling the conversion of
nonstandard product measurements into standard
units via conversion factors are required for a wide
range of commonly purchased products and their
packaging.

Data availability statement

All data that support the findings of this study are
included within the article (and any supplementary
files).

Acknowledgments

This research was undertaken through the ‘Expand-
ing safe water and waste management service access
to off-grid populations in Africa’ project funded
through a UKRI Collective Fund award via the Global
Challenges Research Fund (ref: ES/T008121/1). The
support of the UK Economic and Social Research
Council (ESRC) is gratefully acknowledged.

Author contributions were as follows:
Conceptualisation—JW, AH, HV; Investigation—
MD, QAT, JOO, LO; Writing—Original draft: JW &
PS; writing—review & editing: HV, SD, AH, MD,
JOO, LO, QAT; Formal analysis, visualization—JW,
PS, & HV; Project administration—JW, MD, JOO,
LO; Funding acquisition—JW, AH, HV, JOO, LO,
MD, PS.

Conflict of Interest declaration:

The authors declare that they have NO affiliations
with or involvement in any organization or entity
with any financial interest in the subject matter or
materials discussed in this manuscript.
## Ethical statement

This secondary data analysis of human subjects data was approved by the ethics committee of the Faculty of Environmental and Life Sciences, University of Southampton, UK (Ref: 56 807; approval date: 10 May 2020). All procedures performed in studies analysing data on human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments.

## ORCID iDs

Jim Allan Wright https://orcid.org/0000-0002-8842-2181

Simon Damkjaer https://orcid.org/0000-0002-0758-6038

Heini Vaisanen https://orcid.org/0000-0002-5494-0415

Mawuli Dzodzomenyo https://orcid.org/0000-0002-4709-3182

Allan G Hill https://orcid.org/0000-0002-4418-0379

Lorna Grace Okotto https://orcid.org/0000-0003-0109-3942

Joseph Okotto-Okotto https://orcid.org/0000-0002-4656-8369

Peter Shaw https://orcid.org/0000-0003-0925-5010

## References

[1] Lebreton L and Andrady A 2019 Future scenarios of global plastic waste generation and disposal *Palgrave Commun.* **5** 6

[2] Jambeck J R, Geyer R, Wilcox C, Siegler T R, Perryman M, Andrady A, Narayan R and Law K L 2015 Plastic waste inputs from land into the ocean *Science* **347** 768–71

[3] Tiseo I 2021 Global plastic production 1950–2020 (Hamburg: Statistica) (available at: www.statista.com/statistics/282732/global-production-of-plastics-since-1950/)

[4] Li W C, Tse H F and Fok L 2016 Plastic waste in the marine environment: a review of sources, occurrence and effects *Sci. Total Environ.* **566** 333–49

[5] Hurley R, Horton A, Lusher A and Nizzetto L 2020 Plastic waste in the terrestrial environment *Plastic Waste and Recycling* ed T M Letcher (New York: Academic) ch 7, pp 163–93

[6] Eriksen M, Lebreton L C M, Carson H S, Thiel M, Moore C J, Borerro J C, Galgani F, Ryan P G and Reisser J 2014 Plastic pollution in the world’s oceans: more than 5 trillion plastic pieces weighing over 250,000 tons afloat at sea *PLoS One* **9** e111913

[7] Wright S L, Thompson R C and Galloway T S 2013 The physical impacts of microplastics on marine organisms: a review *Environ. Pollut.* **178** 483–92

[8] Schwabl P, Köppel S, Königshofer P, Bucsics T, Trauner M, Reiberger T and Liebmann B 2019 Detection of various microplastics in human stool *Ann. Intern. Med.* **171** 453–7

[9] Mukhtar E, Williams I and Shaw P 2018 Visibility of fundamental solid waste management factors in developing countries *Detritus* **1** 162–73

[10] Nagpure A S, Ramaswami A and Russell A 2015 Characterizing the spatial and temporal patterns of open burning of municipal solid waste (MSW) in Indian cities *Environ. Sci. Technol.* **49** 12904–12

[11] Kaza S, Yao L, Bhada-Tata P and Van Woerden F 2018 *What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050* (Washington, DC: World Bank)

[12] Carletto C, Zezza A and Banerjee R 2013 Towards better measurement of household food security: harmonizing indicators and the role of household surveys *Glob. Food Secur.* **2** 30–40

[13] Natali L and de Neubourg C 2014 *Household welfare measurement in Bangladesh: a tale of two short consumption modules* 2014-17 (Unicef Office of Research - Innocenti)

[14] United Nations 2018 Classification of individual consumption according to purpose (COICOP) 2018 Division S; Report No. M99 (New York: Department of Economic and Social Affairs)

[15] Wardrop N A, Dzodzomenyo M, Aryeetey G, Hill A G, Bain R E S and Wright J 2017 Estimation of packaged water consumption and associated plastic waste production from household budget surveys *Environ. Res. Lett.* **12** 074029

[16] Ghana Statistical Services, ICF 2020 *Ghana Malaria Indicator Survey 2019* (Accra: Ghana Statistical Services and ICF.)

[17] Stoler J 2012 Improved but unsustainable: accounting for sachet water in post-2015 goals for global safe water *Trop. Med. Int. Health* **17** 1506–8

[18] Robinson J and Howland O 2022 Visible and invisible risks: exploring washing and hygiene practices with women living on low income in Kenya *Glob. Public Health* **17** 1002–15

[19] Akinbami C A O and Momodu A S 2013 Health and environmental implications of rural female entrepreneurship practices in Osun state Nigeria *AMBIO* **42** 644–57

[20] MacArthur R, Teye E and Darkwa S 2021 Quality and safety evaluation of important parameters in palm oil from major cities in Ghana *Sci. Afr.* **13** e00860

[21] Ghana Statistical Service 2019 *Ghana Living Standard Survey (GLSS 7) 2017* (available at: https://www2.statsghana.gov.gh/nada/index.php/catalog/97) (Accessed 1 December 2022)

[22] Kenya National Bureau of Statistics 2022 *Kenya Integrated Household Budget Survey 2015-2016* (available at: https://statistics.knbs.or.ke/nada/index.php/catalog/13) (Accessed 1 January 2022)

[23] Ghana Statistical Services 2018 *Ghana living standards survey round 7: poverty trends in Ghana, 2005-2017* (Ghana Statistical Services)

[24] Kenya National Bureau of Statistics. Basic report 2018 2015/16 *Kenya Integrated Household Budget Survey (KIHBS)* (Nairobi)

[25] StataCorp 2019 Stata statistical software 16 *College Station* (Texas: Statacorp LLC)

[26] Becerril-Arreola R and Bucklin R E 2021 Beverage bottle capacity, packaging efficiency, and the potential for plastic waste reduction *Sci. Rep.* **11** 3542

[27] Sibanda L K, Obange N and Awuor F O 2017 Challenges of solid waste management in Kisumu, Kenya *Urban Forum* **28** 387–402

[28] Muthuuri P, Kassim J, Richard P and Mwarania F 2021 Last mile access to enriched children's complementary food: mitigating malnutrition in Kenya *Front. Public Health* **9** 604864

[29] Valentin M 2010 *Bouteilles et sachets en plastique: pratiques et impacts des modes de consommation d'eau a boire au Senegal* *Autrepart* **55** 57–70

[30] Stoler J, Weeks J R and Fink G 2012 Sachet drinking water in Ghana’s Accra-Tema metropolitan area: past, present, and future *J. Water Sanit. Hyg. Dev.* **2** 223–40

[31] Amazonas M, Fisher G and Zhang W 2018 *Research Shows Which PET Water Bottle Design Attributes Impact Recycling* (Holland, OH: Plastic Technologies Inc.)

[32] Wright J, Dzodzomenyo M, Fink G, Wardrop N A, Aryeetey G C, Adanu R M and Hill A G 2016 Subsidized sachet water to reduce diarrheal disease in young children: a
feasibility study in Accra, Ghana Am. J. Trop. Med. Hyg. 95 239–46

[33] Syrigos A and Adamides E 2022 Environmental and economic assessment of the PET bottles manufacturing process: a case study Sustainable Design and Manufacturing ed S Scholz, R Howlett and R Setchi (Singapore) pp 202–13

[34] European Council 2008 Directive 2008/98/EC of the European parliament and of the council on waste and repealing certain directives, 2008/98/EC

[35] McDonald R I, Douglas I, Revenga C, Hale R, Grimm N Grönwall J and Fekete B 2011 Global urban growth and the geography of water availability, quality, and delivery Ambio 40 437–46

[36] Smith L C and Subandoro A 2007 Measuring food security using household expenditure surveys (Washington, DC: International Food Policy Research Institute) p 147

[37] Smith L C, Dupriez O and Troubat N 2014 Assessment of the Reliability and Relevance of the Food Data Collected in National Household Consumption and Expenditure Surveys (Washington, DC: International Household Survey Network)

[38] Deaton A and Grosh M 2000 Consumption Designing Household Survey Questionnaires for Developing Countries: Lessons from 15 Years of the Living Standards Measurement Survey ed M Grosh and P Glewwe (Washington, DC: World Bank) pp 91–134

[39] Schundeln M 2018 Multiple visits and data quality in household surveys Oxf. Bull. Econ. Stat. 80 380–405

[40] FAO, World Bank 2018 Food Data Collection in Household Consumption and Expenditure Surveys: Guidance for Low and Middle Income Countries (Rome: Food and Agriculture Organisation)

[41] Sohrabpour V, Hellstrom D and Jahre M 2012 Packaging in developing countries: identifying supply chain needs J. Humanit. Logist. Supply Chain Manage. 2 183–204

[42] Shaw P J, Lyas J K and Hudson M D 2006 Quantitative analysis of recyclable materials composition: tools to support decision making in kerbside recycling Resour. Conserv. Recycl. 48 263–79

[43] Farfán G, Genoni M E and Vakis R 2017 You are what (and where) you eat: capturing food away from home in welfare measures Food Policy 72 146–56

[44] Mbiba B 2014 Urban solid waste characteristics and household appetite for separation at source in Eastern and Southern Africa Habitat Int. 43 152–62

[45] Perez-Heydrich C, Warren J L, Burgert C R and Emch M E 2013 Guidelines on the Use of DHS GPS Data Contract No. SAR8 (Calverton, MD: ICF International)

[46] Oseni G, Durazo J and McGee K 2017 The Use of Non-Standard Units for the Collection of Food Quantity: A Guidebook for the Measurement of Food Consumption and Agricultural Production in Living Standards Surveys (Washington, DC: World Bank)

[47] Frankenberg E 2000 Community and price data Designing Household Survey Questionnaires for Developing Countries: Lessons from 15 Years of the Living Standards Measurement Survey ed M Grosh and P Glewwe (Washington, DC: World Bank) pp 315–38

[48] Miezah K, Obiri-Danso K, Kádár Z, Fei-Baffoe B and Mensah M Y 2015 Municipal solid waste characterization and quantification as a measure towards effective waste management in Ghana Waste Manage. 46 15–27