Beach pollution from marine litter: Case of six beaches in the Limbe and Kribi municipalities of Cameroon

Lawrence O. Mbeng 1*, David. Mboglen1 and George Y. Chiambeng2
1The University of Douala, Institute of Fisheries and Aquatic Sciences at Yabassi, PO Box 7236, Douala, Cameroon
2Research station for fisheries and oceanography, Batoke PO Box 77, Limbe, Cameroon
Beach pollution from marine litter

Abstract

The aim of this research paper is to assess beach pollution from marine litter involving three beaches in the Limbe municipality ( Idenau, Semme and IRAD) and the Kribi municipality
 ( Londji II, Nziou and Ngoye) between  May and September 2014. The methodology consisted of a beach survey and a waste composition study using direct observation and mechanical and electronic balance. Laboratory analysis of fecal coliform was carried out to determine the ecological and human health impacts; Questionnaires were used to determine public perception on the phenomenon of beach pollution by marine litter. Waste composition study revealed that the fishing beaches of Idenau were heavily polluted with wood fragments (28, 0%), plastics (23, 8%) and 7.1% for others like fruits of nypas spp while  for Londji II,  wood fragments (22, 7%), plastics (20, 5%) and 4.6% for others like fruits of nypas spp. From questionnaire analysis, 78, 6% of respondents in the Limbe beaches and 81, 8% in the Kribi beaches  mentioned old and abandoned canoes, fishing nets, plastics and plant debris as the main sources of beach pollution. The results also revealed that Idenau and Londji II beaches were highly contaminated with fecal coliform within a range of 4730 – 5980 CFU/100ml and 3170–4150 CFU/100ml respectfully, not in line with U.S. Environmental Protection Agency (USEPA) and World Health Organization (WHO) recommendations for drinking, swimming, boating and fishing. Many stakeholders agreed on an integrated approach involving education and sensitization with practical exercises of beach clean-ups and maintenance. 

Keywords: Beach pollution, marine litter, waste composition, perception, fecal colliform
  1. INTRODUCTION
Most significant sources and studies describe amounts of marine litter in terms of "number of items", as most data stems from monitoring beach litter. Volumes (in kg or m³) have been highlighted in some studies, although not often (Eduard et al., 2013). This is important, since the "number of items" (and resulting percentages regarding most prevalent marine litter types) do not necessarily reflect the importance of the items in terms of impacts (Eduard et al., 2013). Moreover, all monitoring results depend very much on the state of affairs prevailing on the day of the survey (i.e. weather condition including wind direction, timing of the last survey or cleaning event etc.) and in the area (i.e. currents, distance to sources etc.), making data aggregation and up-scaling difficult (Eduard et al., 2013).
This paper presents the results of beach pollution by marine litter using three beaches each from Limbe municipality in the South West Region and kribi municipality in the South Regions of Cameroon.  Data from these case study areas reveal that marine litter and fecal colliforms affect the ecological health of beaches, tourism and fishing activities.
1.1 AN OVERVIEW OF BEACH SURVEYS
Beach survey is one of several methods used to observe marine litter in the marine environment which however varies with sampling protocols. For example, they can record the number of items and/or the mass of waste (Figure 1), and can differ in the areas covered by Oslo Paris Convention for Protection of the Marine Environment of the North-East Atlantic (OSPAR).
Figure 1: Composition and numbers of marine litter items found on beaches within OSPAR network.  Source: (OSPAR, 2009)
Plastic litter on OSPAR beaches fluctuated between 2001 and 2006 with no discrete pattern. The composition of the plastic litter also changed, particularly for plastic/polystyrene (OSPAR, 2009) (Figure 2).

Figure 2: Changes in composition of marine items found on beaches within OSPAR network.
 Source: (OSPAR, 2009)


1.2 STUDY AREA
Cameroon is located in the Gulf of Guinea between Gabon, Equatorial Guinea and Nigeria with 15.7 million inhabitants covering an area of 475,000 km2 (Human Development Report, 2006). This gives the country a wide geographical and ecological diversity favorable for the growth of different fish species. Cameroon has great potential with 420 km of maritime coast, mangrove forest, lagoons and many beaches (Agardy, 1994).
Limbe is a coastal town and an economic center of the South-West Region of Cameroon. It has a population of about 150,000 inhabitants and a land area of 596 km2 (National Institute of Statistics, 2007). It is bordered to the West by the Idenau / 4.00; 9.22District, East by Mutengene, North by Buea, and to the South by the Atlantic Ocean.  Cameroon beaches are described as ‘LUNGS’ of the economy due to their high productivity, lodging a majority of the economic activities. Kribi is a coastal town in the South Region of Cameroon, with Kribi 1 municipality having 33,298 inhabitants and Kribi II 39,156 inhabitants.
This paper highlights six prominent beaches in the Limbe and Kribi municipalities; the effect of pollution from marine litter and its impacts on the economy, public health and tourism.
1.3 ECOLOGIC IMPACTS OF MARINE LITTER
Negative effects have been reported such as interfering in the ability of marine organisms to capture and digest food, sense hunger, escape from predators and reproduce, decreasing body condition and locomotion and migration. According to the Convention on Biological Diversity (CBD, 2012), ingestion of micro plastics can provide a pathway for transport of harmful chemicals.
1.3.1 INGESTION AND ENTANGLEMENT
Impacts of marine litter involving entanglement and ingestion (Table 1) were reported for 663 species representing a 40% increase since the last review in 1997 (Laist, 1997; Mudgal et al., 2011).  About 43% of existing cetacean species, all species of marine turtles, about 44% of the world’s seabird species, and many species of fish have been reported to ingest marine litter (Katsanevakis, 2008).

According to the 1998 U.S. Marine Mammal Commission´s last published report in 1999, 136 marine species were reported in entanglement incidents, including six of the seven species of sea turtle, 51 out of the world´s 312 species of seabirds, and 32 species of marine mammals. Of the 120 marine mammals species listed on the International Union for the Conservation of Nature (IUCN) list, 54 (45%) were reported to have interacted (ingestion and/or entanglement) with marine litter (Laist, 1997).  About 15% of the species affected through entanglement and ingestion are in the IUCN Red List, with some harmed, already dead and many with sub-lethal effects that have not been fully reported (CBD, 2012). For example, litter on beaches has been shown to adversely affect the ability of turtle hatchlings to reach the Mediterranean Sea with two of three turtles having contact with litter on their way to reach the water (Triessnig et al., 2012).

Table 1: Marine species with documented entanglement and ingestion records
Source: (Laist, 1997; Mudgal et al., 2011).
                                 Species groupTotal number of species worldwideNumber and % of species with entanglement recordsNumber and % of species with ingestion records
Sea turtles76(86%)6(86%)
Sea birds31251(16%)111(36%)
Penguins166(38%)1(6%)
Grebes192(10%)0
Albatrosses, petrels, shearwaters9910(10%)62(63%)
Pelicans, boobies, gannets, cormorants, frigate birds, tropic birds5111(22%)8(16%)
Shorebirds, skuas, gulls, terns, auks11222(18%)40(33%)
Other birds50
Marine mammals11532(28%)26(23%)
Baleen whales106(60%)2(20%)
Toothed whales655(8%)21(32%)
Fur seals and sea lions1411(79%)1(7%)
True seals198(42%)1(5%)
Manatees and dugongs41(25%)1(25%)
Sea utter11(100%)0
Fish3433
Crustaceans80
Squid01
Species total 136177


1.4.2 IMPACTS ON HABITATS
Impacts of marine litter on habitats include alteration, damage and degradation of benthic habitats such as coral reef and soft sediment abrasion from derelict fishing gear or smothering from macro and micro plastics on sandy sediments in the intertidal zones (Katsanevakis et al., 2007; Richards and Beger, 2011). Litter can disrupt the assembly of organisms living on or in the sediment (Chiappone et al., 2002).
Plastic litter also affects beaches in that these habitats can support diverse, marginal invertebrate species, visited by many vertebrates, mostly birds who use plastic litter as nesting material. Litter also displace species that live in unspoiled beach conditions and affect the ability of wildlife to find food. For example research in the Philippines showed that the efficiency of the gastropod Nassarius pullus to locate and move towards a food item decreased as the level of plastic litter increased on the beach (Aloy et al., 2011).

1.4.3 ECONOMIC AND SOCIAL IMPACTS
Although information on the economic impacts of marine litter on beaches is relatively scarce, some reports (Brink et al., 2009; Mouat et al., 2010) have indicated the economic impacts of marine litter on coastal communities.
  • Sanitary towels, condoms and cotton buds, degrade the quality of the bathing water and may present a health risk;
  • Hazardous materials such as medical wastes, syringes, glass and other sharp and/or dangerous (munitions) items that is washed-up on beaches with direct risks to beachgoers.
UK municipalities for example spend approximately €18 million each year removing beach litter, a 37% increase in cost over the past 10 years. Netherlands and Belgium also spend approximately €10.4 million per year (Mouat et al., 2010).
One of the major economic issues motivating the need for clean-up operations is the aesthetic impact on tourist beaches. The direct costs to the fishing industry are also very important, including: loss of fish stocks due to ghost fishing.  Others include spoiled catches through contamination with litter, but also with paint and oil; damage to nets and to propellers, entangled in litter, resulting in lost operating time and time spent cleaning nets (Tinch et al., 2012).  Mindful of the fact that coasts and oceans provide food and tourism opportunities, aesthetic, economic and environmental issues caused by marine litter can have wider social impacts, especially where the livelihood and health of local coastal communities are affected (Tinch et al., 2012).
1.4.4 HEALTH IMPACTS
The range of non-fecal bacteria represented in the coliform group and the environmental growth of thermophilic fecal coliforms  e.g. Klebsiella  spp and E. coli have disturbed bacteriologists and sanitary engineers since the 1930s. Despite the obvious failings of the total coliform group to indicate health risk from bacterial pathogens, they provide important information on process efficiency which is clearly essential in relation to health protection (Ashbolt et al., 1997; Camper et al., 1991).
Many members of the total coliform group and some fecal coliforms e.g. Klebsiella spp and  Enterobacter spp are not specific to faeces, and even E. coli  has been shown to grow in some natural aquatic environments (Ashbolt et al., 1997; Camper et al., 1991;  Bermudez and  Hazen, 1988; Hardina and Fujioka, 1991; Niemi et al., 1997; Solo-Gabriele et al.,  2000 ; Zhao et al., 1997).  It is on this basis that water use e.g. for drinking, swimming, boating or fishing must conform to USEPA and WHO recommendation (Table 2).
Table 2: Fecal coliform (CFU/100ml) standards. Source: (APHA, 1992; Frenk and  Murray, 1999).
Water UseDesirable Level (CFU/100ml)Permissible Level (CFU/100ml)
Drinking00
Swimming<200<200
Boating or fishing<1000<5000
Direct observation revealed open air defecation both by children and adolescence. Many of the so called latrines were makeshift structures (Plate 1) which increases the risks of high fecal contamination on water use e.g. drinking, swimming, boating or fishing. The presence of traditional ovens closer to these beaches (Plate 2) aggravated the problem of beach pollution because no litter collection bins were available at the site during our visits.

 Plate 1. Makeshift toilets                               Plate 2.   Traditional smoked fish ovens             


  1. MATERIALS AND METHODES
The methodology consisted of a beach survey involving a demarcation of the area of study to 500m2 that is 50m along the beach and 10m from the low tide mark towards the emerging vegetation. Waste composition study was undertaken using direct observation and mechanical balance for voluminous marine litter and electronic balance for light marine litter.
 Laboratory analysis of fecal coliform bacteria was carried out to determine the ecological and health impacts of human and animal feaces.  Water samples were collected once each month for three consecutive months, conserved under ice at 4oC followed by laboratory analysis within a 24 hour period as recommended by (USEPA, 1985; ALPHA, 1992).

 Questionnaires administered to fishermen, tourists and public health personnel’s was to  determine perception, attitudes and beliefs on the phenomenon of beach pollution from marine litter, its impact on fishing activities, human health, the economy and tourism.  The 96 individuals randomly picked during the survey period (May to September 2014) were between the ages of 16 and 60. Of the 86 persons who agreed to participate, 36 (41.9%) were fishermen, 26 (30.2 %) tourists and 24 (27.9 %) public health personnel’s.
  1. RESULTS AND DISCUSSION
The composition and characterization of beach litter is an important aspect of solid waste management and planning where information is required by local authorities to develop litter management strategies at beaches. Variation in the composition and characteristics of marine litter provided us with a clue to better understand its impact on beaches.  Questionnaires analysis gave evidence on perception, attitudes and beliefs on the phenomenon of beach pollution from marine litter, its impact on fishing, human health and tourism.
 3.1 COMPOSITION OF BEACH LITTER
The results of our composition study as indicated in Figure 3 for the Limbe beaches (Idenua, Semme and IRAD) showed wood fragments (28, 0%) as the most dominant and plastics (23, 8%), and others (7, 1%) with fruits of nypas spp as the dominant fraction. These results differ from (Folack, 1989), with fruits of Nypas spp as the dominant beach litter followed by plastics in the Batoke, Mile 6 and SONARA beaches of the South West Region of Cameroon. The results also differ from OSPAR network with plastics being the dominant type of beach litter (OSPAR, 2007).
Figure 3: Average % composition of  litter in the Limbe beaches

The beaches in the Kribi municipality (Longji II, Ngoye and Nziou) showed a similar trend with regards to the composition of the beach litter (Figure 4) with wood fragments (22, 7%) as the most dominant,  plastics (20, 5%), and others (4, 6%), with fruits of nypas spp as the dominant fraction.
Figure 3: Average % composition of litter in the Kribi beaches

The beaches in the Kribi municipality (Longji II, Ngoye and Nziou) showed a similar trend with regards to the composition of the beach litter. The results of the composition study (Figure 4), shows wood fragments (22, 7%) as the most dominant beach litter followed by plastics(20,5%), with the Others (4,6%), having a significant proportion of fruits of nypas spp.
Figure 4: Average % composition of marine litter for Kribi beaches


3.2 FACTORS LINKED TO THE VARIATION OF BEACH LITTER
Variations in the monthly average percentage composition (July, August, and September) of litter at the Idenua, IRAD and Semme beaches were a function of location and historical ties; seasonality and economic activities. Idenau beach was the most polluted with litter followed by IRAD, with Semme being the least polluted during the survey period July, August, and September (Figure 5). On the basis of location and historical ties, Idenau is a fishing beach in the South West Region of Cameroonn, close to Nigeria, with its economic importance as a trading centre for consumer goods. Historically, a majority of the population are undocumented Nigerians and Beninois fishermen and traders. In the absence of permanent residency, there are many temporal accommodations with some just a few meters away from the beach. The absence of good sanitary facilities like toilets is the main reason why human faeces could be seen at the vicinity of the beach (Plate 1).

Figure 5: Monthly average percentage composition of marine litter for Limbe beaches
The results of the study show a strong relationship between seasonality and economic activities. In Figure 3, the monthly average percentage composition marine litter in the Limbe beaches was more dominant in the months of July, August and September. This was confirmed by meteorological readings which showed the months of July and August with the highest rainfall of 700mm. Added to this is the fact that Idenua is located a few kilometers from Dibuncha, considered one of the wettest places in the planet. From direct observations at the Idenua beach, we found the construction of fishing boats, and the illegal trafficking of petroleum products from Nigeria to Cameroon with negative impacts on tourism, swimming, boating or fishing.
The differences in our analysis between IRAD and the Semme beach, stems from the fact that Semme beach has the best hotels in the South West Region of Cameroon named the Semme beach hotel; hence in order to maintain its aesthetic values,  clean ups are done on a regular basis.  It is for this reason that our results showed very low levels of pollution.
The high pollution at the Londji II beach in the months of July, August and September (Figure 6) is linked to seasonality with high precipitation in the months of July, August and September. In addition is the construction of canoes, boats and the movements of goods and services into and out of Kribi.  Being the main touristic destination in Cameroon, Kribi receives more tourists than any other municipality in Cameron. The kribi seaport which is presently under construction attracts workers from within and outside Cameroon. The influx of migrant workers has had great impact on the beaches especially during the weekends for leisure. Our analysis also showed that pollution at the Ngoye and the Nziou beaches were also a function of seasonality and economic activity..

Figure 6: Monthly average percentage composition of marine litter for Kribi beaches

3.3 PERCEPTION OF MARINE LITTER AND FISHING ACTIVITIES
Results from questionnaire analysis on public perception of marine litter as the source of beach pollution, showed 78, 6% of fishermen in Limbe (Figure 7) and 81, 8% of fishermen in Kribi (Figure 8) responded positively and acknowledge wood fragments, old and abandoned canoes, fishing nets, plastics and fruits of nypas spp as the main deterrents to fishing. Although 21, 4% of the Limbe fishermen and 18, 2% of the kribi fishermen responded negatively, they acknowledged the presence of beach litter but indicated that the source was a manifestation of the gods of the ocean.  Beach pollution was not considered a recent phenomenon as indicated from the responses. This is because many fishermen indicated that for centuries their parents and grandparents have constantly witnessed the manifestation of beach pollution from marine litter but with little or no knowledge of the sources or sustainable solutions of managing beach litter. Notwithstanding, respondents from Limbe were more familiar with regards to the sources of beach pollution by marine litter.
Figure 7: Public perception of pollution at the Limbe beaches
Figure 8:   Public perception of pollution at the Kribi beaches


3.4 PERCEPTION OF BEACH LITTER AND PUBLIC HEALTH
Results from questionnaire analysis indicates that, diarrhoea (41.7%) and fever 33.3% (Figure 9) were the most prevalent health condition, with children (58,2%) and adolescence (25,4%) more vulnerable to these diseases (Figure 10). Diarrhoea is one of the most important global public health problems, the third highest contributor to the global burden of disease in 1998 (Frenk and Murray, 1999).  Diarrhoea is amongst the main causes of morbidity and mortality among children in developing countries with about 4.9 in 1000 children under five dying from diarrhoea every year (1.6 to 2.5 million deaths per year); each child under five has an average 3.2 episodes of diarrhoea per year (Kosek et al., 2003). Direct observation in the field confirm this results because children under five spend most of their valuable time after school playing on the beach.
Figure 9: Percentage prevalence of diseases caused by exposure to beach litter
Figure 10: Percentage vulnerability of different age groups to beach litter


3.6.1 FECAL COLLIFORM FROM BEACH LITTER
Fecal Colliform analysis of beach litter showed that the average fecal CFU/100ml concentration for all the six sampled beaches of Limbe and kribi ranges between 220 – 5980 CFU/100ml (Table 3). This  fecal  coliform  count  range  is  far  above  recommended  standard (USEPA, 1985; WHO, 1984; WHO,1998; WHO, 2001). Due to the fact that some locals at the beaches were solely dependent on beach water for domestic use, disease prevalence was a common scenario. Makeshift toilets and traditional smoked fish ovens (Plates 1&2) located too close to the beaches coupled with the unrestricted movements of  domestic animals e.g. goats, pigs, dogs and cats etc made  situation even worse. The absence of a proper domestic waste collection bins and a disposal strategy even aggravated the situation. This is in line with (Cointreau-Levine, 1982; UNEP, 1996; Zubrugg, 2003), highlighting problems in developing countries emanating from the mixing of human and animal excreta with domestic waste.
Table 3: Fecal Coliform counts (July, Augustan, September) for Limbe and Kribi beaches
BeachesCFU/100ml
MInimum
Average
Reading
CFU/100ml
Maximum
Average
Reading
Idenua47305980
Semme359618
IRAD10802118
Londji II31704150
Ngoye275318
Nziou2201072
In spite of some evidence linking the occurrence of child diarrhoea and deficiencies in environmental sanitation, especially the lack of an adequate sewerage system and also the quality and quantity of water for human consumption, there are gaps in the knowledge of the relationship between environment and human health (Huttly et al., 1997; Bradley et al., 1992).


3.5 PERCEPTION OF BEACH LITTER AND TOURISM
Results from questionnaire analysis, interviews with fishermen and hotel operators as well as direct observation in the field revealed that Idenau and Londji 11 beaches had the lowest number of tourist visits by virtue of the level of beach pollution from marine litter.
  1. CONCLUSION
This paper presents the results of pollution by marine litter using three beaches each from the Limbe municipality of the South West Region and Kribi municipality of the South Region of Cameroon.  Results obtained so far indicates that the composition of beach litter, it’s ecological, social, economic and health impacts cannot be underestimated in a developing country like Cameroon. To prevent these impacts, users must consider marine litter as a pollutant on the same level as heavy metals, chemicals and oil (Mouat et al., 2010; Tinch et al., 2012), which would then give it the same political credibility.  In the same light, (Brink et al., 2009), used market-based instruments to address the problem of beach pollution from marine litter. These include:
  • Applying the polluter pays principle, in terms of fines for littering, dumping waste and illegal disposal;
  • Applying the user pays principle, in terms of tourist taxes, car park fees, port reception and ship berthing fees. These can contribute to beach cleaning and improving waste infrastructure;
  • Incentives to fishermen for reporting on and removing debris, for example the ‘Fishing for Plastic’ project in the Save our North Sea programme, which pays fishermen to remove plastic;
  • Financial and technical support for installing waste management systems on board fishing vessels, leisure crafts and larger ships with inadequate facilities;
  • Award based incentives for coastal villages with Integrated Waste Management Systems, which incorporate all the policies, programmes and technologies that are necessary to manage the entire waste stream.
  1. RECOMMENDATIONS
  • Raising awareness of the importance of beaches should target both the direct and indirect users. Direct users include tourists, fishermen and the researchers while the indirect users include children and adolescence that use the beaches for fun with little or no knowledge of its ecological, economic, and social and health importance. Education should be complemented with practical exercises involving all and sundry in beach clean-ups and maintenance.
  • The ‘Others’ with fruits of nypas spp being the most dominant category should be analyzed in the laboratory in-order to determine their medicinal and infrastructural values.
  • Composition and characterization studies on marine litter be carried out on both seasons (dry and rainy) for it will provide us with the clue to better understand the influence of seasonal variations on marine litter and its impact on Cameroonian beaches.
COMPETING INTEREST
No competing interests exist
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