Jumat, 15 Mei 2009

Water-related diseases (Cyanobacterial Toxins)

Cyanobacterial Toxins

Cyanobacteria or blue-green algae occur worldwide especially in calm, nutrient-rich waters. Some species of cyanobacteria produce toxins that affect animals and humans. People may be exposed to cyanobacterial toxins by drinking or bathing in contaminated water. The most frequent and serious health effects are caused by drinking water containing the toxins (cyanobacteria), or by ingestion during recreational water contact.

The disease and how it affects people

Disease due to cyanobacterial toxins varies according to the type of toxin and the type of water or water-related exposure (drinking, skin contact, etc.). Humans are affected with a range of symptoms including skin irritation, stomach cramps, vomiting, nausea, diarrhoea, fever, sore throat, headache, muscle and joint pain, blisters of the mouth and liver damage. Swimmers in water containing cyanobacterial toxins may suffer allergic reactions, such as asthma, eye irritation, rashes, and blisters around the mouth and nose. Animals, birds, and fish can also be poisoned by high levels of toxin-producing cyanobacteria.

The cause


Cyanobacteria are also known as blue-green algae, so named because these organisms have characteristics of both algae and bacteria, although they are now classified as bacteria. The blue-green colour comes from their ability to photosynthesize, like plants.
Cyanobacterial toxins are classified by how they affect the human body. Hepatotoxins (which affect the liver) are produced by some strains of the cyanobacteria Microcystis, Anabaena, Oscillatoria, Nodularia, Nostoc, Cylindrospermopsis and Umezakia. Neurotoxins (which affect the nervous system) are produced by some strains of Aphanizomenon and Oscilatoria. Cyanobacteria from the species Cylindroapermopsis raciborski may also produce toxic alkaloids, causing gastrointestinal symptoms or kidney disease in humans. Not all cyanobacteria of these species form toxins and it is likely that there are as yet unrecognized toxins.
People are mainly exposed to cyanobacterial toxins by drinking or bathing in contaminated water. Other sources include algal food tablets. Some species form a scum on the water, but high concentrations may also be present throughout the affected water. Surface scums, where they occur, represent a specific hazard to human health because of their particularly high toxin contact. Contact, especially by children, should be avoided.

Distribution


The organisms can grow rapidly in favourable conditions, such as calm nutrient-rich fresh or marine waters in warm climates or during the late summer months in cooler parts of the world. Blooms of cyanobacteria tend to occur repeatedly in the same water, posing a risk of repeated exposure to some human populations. Cyanobacterial toxins in lakes, ponds, and dugouts in various parts of the world have long been known to cause poisoning in animals and humans; one of the earliest reports of their toxic effects was in China 1000 years ago (Chorus and Bartram, 1999).

Scope of the Problem


Cyanobacteria have been linked to illness in various regions throughout the world, including North and South America, Africa, Australia, Europe, Scandinavia and China. There are no reliable figures for the number of people affected worldwide. The only documented and scientifically substantiated human deaths due to cyanobacterial toxins have been due to exposure during dialysis. People exposed through drinking-water and recreational-water have required intensive hospital care.

Interventions

* Reducing nutrient build-up (eutrophication) in lakes and reservoirs, especially by better management of wastewater disposal systems and control of pollution by fertilizers (including manure) from agriculture.
* Educating the staff in the health and water supply sectors, as well as the public, about the risks of drinking, bathing or water sports in water likely to contain high densities of cyanobacteria.
* Water treatment to remove the organisms and their toxins from drinking-water supplies, where appropriate.

References

Toxic Cyanobacteria in Water: a guide to their public health consequences, monitoring and management, edited by J. Bartram& I. Chorus. Geneva, World Health Organization, 1999.
Prepared for World Water Day 2001. Reviewed by staff and experts at the Federal Environmental Agency, Germany, and the Water, Sanitation and Health Unit (WSH), World Health Organization (WHO), Geneva.



jika diterjemahkan dengan "google translate" kurang lebih seperti ini :



Cyanobacterial Toxins

Cyanobacteria atau biru-hijau algae terjadi di seluruh dunia terutama dalam tenang, gizi kaya air. Beberapa spesies cyanobacteria memproduksi toxins yang mempengaruhi hewan dan manusia. Orang mungkin akan menemukan cyanobacterial toxins oleh minum atau mandi di air ketularan. Yang paling sering dan serius efek kesehatan yang disebabkan oleh air minum yang mengandung toxins (cyanobacteria), atau selama proses menelan rekreasi air kontak.

Penyakit dan bagaimana akan mempengaruhi orang-orang

Penyakit akibat cyanobacterial toxins bervariasi sesuai dengan jenis toksin dan jenis air atau air yang terkait dengan eksposur (minum, kulit kontak, dll). Manusia akan terpengaruh dengan berbagai gejala, termasuk iritasi kulit, keram perut, muntah, mual, diare, demam, sakit tenggorokan, sakit kepala, sakit otot dan sendi, blisters dari mulut dan kerusakan hati. Berenang di air yang mengandung cyanobacterial toxins Mei menderita reaksi alergi, seperti asma, mata iritasi, rashes, dan blisters sekitar mulut dan hidung. Binatang, burung, dan ikan juga dapat keracunan oleh tingginya tingkat produksi toksin-cyanobacteria.

Penyebab

Cyanobacteria yang juga dikenal sebagai algae biru-hijau, sehingga bernama karena organisme memiliki karakteristik dari kedua algae dan bakteri, walaupun mereka sekarang diklasifikasikan sebagai bakteri. Biru-warna hijau berasal dari kemampuan mereka untuk photosynthesize, seperti tanaman.
Cyanobacterial toxins diklasifikasi oleh pengaruhnya terhadap tubuh manusia. Hepatotoxins (yang mempengaruhi hati) yang diproduksi oleh beberapa jenis dari cyanobacteria Microcystis, Anabaena, Oscillatoria, Nodularia, Nostoc, Cylindrospermopsis dan Umezakia. Neurotoxins (yang mempengaruhi sistem saraf) yang diproduksi oleh beberapa jenis dari Aphanizomenon dan Oscilatoria. Cyanobacteria dari spesies Cylindroapermopsis Raciborski Mei juga menghasilkan racun alkaloids, gastrointestinal menyebabkan gejala ginjal atau penyakit pada manusia. Tidak semua spesies cyanobacteria ini formulir toxins dan kemungkinan yang ada namun tidak dikenal sebagai toxins.
Terutama orang yang terkena cyanobacterial toxins oleh minum atau mandi di air ketularan. Sumber lain termasuk makanan algal tablet. Beberapa spesies membentuk buih di atas air, konsentrasi tinggi, tetapi juga dapat hadir di seluruh terkena air. Permukaan scums, di mana mereka terjadi, mewakili tertentu bahaya untuk kesehatan manusia karena tinggi terutama toksin kontak. Kontak, terutama oleh anak-anak, harus dihindari.

Distribusi

Organisme yang dapat tumbuh dengan cepat dalam kondisi baik, seperti gizi tenang kaya laut segar atau air hangat iklim atau selama akhir bulan-bulan musim panas dingin di belahan dunia. Mekar dari cyanobacteria cenderung terjadi berulang kali di air yang sama, hal yang berulang eksposur risiko untuk beberapa populasi manusia. Cyanobacterial toxins di danau, kolam, dan dugouts di berbagai belahan dunia telah lama diketahui menyebabkan keracunan pada hewan dan manusia, salah satu dari laporan awal mereka adalah racun efek di Cina tahun 1000 lalu (Chorus dan Bartram, 1999).

Cakupan Masalah

Cyanobacteria telah dihubungkan dengan penyakit di berbagai daerah di seluruh dunia, termasuk Amerika Utara dan Selatan, Afrika, Australia, Eropa, Skandinavia dan Cina. Tidak ada angka diandalkan untuk jumlah orang yang terkena dampak di seluruh dunia. Satu-satunya dan didokumentasikan secara ilmiah substantiated kematian manusia akibat cyanobacterial toxins telah karena eksposur selama dialysis. Orang yang terpapar melalui air minum dan rekreasi air yang diperlukan perawatan intensif di rumah sakit.

Intervensi

* Mengurangi gizi build-up (eutrophication) di danau dan waduk, terutama oleh manajemen yang lebih baik dari sistem pembuangan limbah dan pengendalian pencemaran oleh pupuk (termasuk pupuk) dari pertanian.
* Mendidik staf dan kesehatan di sektor air, serta masyarakat, tentang risiko minum, mandi atau olahraga air di air mungkin mengandung densities tinggi dari cyanobacteria.
* Air perawatan untuk menghapus organisme dan toxins dari pasokan air minum, jika sesuai.

Referensi

Cyanobacteria racun dalam Air: panduan mereka konsekuensi kesehatan masyarakat, monitoring dan manajemen, diedit oleh J. Bartram & I. Chorus. Jenewa, World Health Organization, 1999.
Disiapkan untuk Hari Air Dunia 2001. Ditinjau oleh staf dan tenaga ahli di Badan Lingkungan Federal, Jerman, dan Air, Sanitasi dan Kesehatan Unit (WSH), Organisasi Kesehatan Dunia (WHO), Jenewa.

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