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There still is an INR 50 ticket available but buying that would restrict you from entering the main mausoleum. This means you will only be able to move around the monument, see the back side, and the Yamuna riverfront.
Pollution caused by vehicles and toxins dumped in the Yamuna river (one of the most polluted rivers of the world), environmental degradation, and an increasing number of tourists have taken a toll on the Taj. Talks for the conservation of the monument have always been in the news. The damage is now considered to be irreversible as officials have failed to stop the ivory white marble from turning pale yellow.
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The Supreme Court of India even threatened to shut down the monument due to the failure of the officials to protect and conserve it. The court also suggested the officials seek international help in speeding the conservation process.
Being a fine example of Mughal architecture, a UNESCO world heritage site and one of the 7 wonders of the world, the Taj Mahal may now be a sight too 'expensive' to behold!