lack of competitiveness was due to the "impossibility to expand the facilities because of lack of space". The metropolitan area of Naples is limited by two dangerous areas, the Mount Vesuvius to the east, and the Campi Flegrei to the west, leaving little space in proximity of the sea. Other large plants were also closed, e.g. Eternit, Q8 oil refinery, ICMI, Sofer, Whirlpool, Olivetti. There is no valuable small and medium enterprises in machine building, metalworking and chemical. Food and agriculture Campania mainly produces fruit and vegetables, but has also expanded its production of flowers grown in greenhouses, becoming one of the leading regions of the sector in Italy. The value added of this sector represents around 6.5% of the total value added of the region, equalling €213.7 million. Campania produces over 50% of Italy's nuts and is also the leader in the production of tomatoes, which reaches 1.5 million tonnes a year. A weak point for the region's agriculture is the very reduced size of farms, equal to 3.53 hectares. Typical products are: A distinctive point of regional agriculture in the breeding of buffalos. The milk is used to produce mozzarella di bufala. Olive trees, mainly of the varieties Carpellese (PDO designated), Cornia (Val di Cornia DOC), Frantoio, Leccino, Ogliarola Barese, Olivella, Ortice, Pisciottana (Also Ogliastrina or Olivo dell'Ascea), Ravece (also known as Rotondello), and Salella, covers over . Vineyards cover 41,129 ha, but only ca. 5,100 ha using to produce quality wine of DOC and DOCG types. There are 4 DOCG wines: Aglianico del Taburno (red and rose), Fiano di Avellino (white), Greco di Tufo (white and sparkling) and Taurasi (red). Wine production has increased as well as the quality of the wine. There is a problem with illegal toxic waste dump in the Triangle of death north of Naples between Acerra, Nola and Marigliano. In the region, over 12,000 cattle, river buffaloes and sheep had been culled before 2006. High levels of mortality and abnormal foetuses were also recorded in farms in Acerra linked to elevated levels of dioxin. Local studies have shown higher than permissible levels of lead in vegetables grown in the area. The government blames the Mafia's illegal garbage disposal racket. In samples of milk, which is using to produce mozzarella di bufala, found cancerogenic dioxine. In Naples-Bagnoli is an asbestos contamination from former Eternit cement plant. Millions of tons of toxic industrial waste